On installing a develop version: self.ld_version is None
#### Code Sample, a copy-pastable example if possible

I followed the rules described at [the docs](https://pandas.pydata.org/pandas-docs/stable/contributing.html#contributing-dev-env). The only thing which differs is that I have Visual Studio 2017 installed. Of course I added Python support for it.

#### Problem description

I either issue the command `python setup.py build_ext --inplace` or the command `python setup.py develop` and end up with an invalid comparison

#### `python setup.py build_ext --inplace`

	running build_ext
	Traceback (most recent call last):
	  File "setup.py", line 740, in <module>
		**setuptools_kwargs)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\core.py", line 148, in setup
		dist.run_commands()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\dist.py", line 955, in run_commands
		self.run_command(cmd)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\dist.py", line 974, in run_command
		cmd_obj.run()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\site-packages\Cython\Distutils\old_build_ext.py", line 186, in run
		_build_ext.build_ext.run(self)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\command\build_ext.py", line 308, in run
		force=self.force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\ccompiler.py", line 1031, in new_compiler
		return klass(None, dry_run, force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\cygwinccompiler.py", line 285, in __init__
		CygwinCCompiler.__init__ (self, verbose, dry_run, force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\cygwinccompiler.py", line 129, in __init__
		if self.ld_version >= "2.10.90":
	TypeError: '>=' not supported between instances of 'NoneType' and 'str'

#### `python setup.py develop`

	running develop
	running egg_info
	writing pandas.egg-info\PKG-INFO
	writing dependency_links to pandas.egg-info\dependency_links.txt
	writing requirements to pandas.egg-info\requires.txt
	writing top-level names to pandas.egg-info\top_level.txt
	reading manifest file 'pandas.egg-info\SOURCES.txt'
	reading manifest template 'MANIFEST.in'
	no previously-included directories found matching 'doc\build'
	warning: no previously-included files matching '*.so' found anywhere in distribution
	warning: no previously-included files matching '*.pyd' found anywhere in distribution
	warning: no previously-included files matching '*.pyc' found anywhere in distribution
	warning: no previously-included files matching '*~' found anywhere in distribution
	warning: no previously-included files matching '#*' found anywhere in distribution
	warning: no previously-included files matching '.DS_Store' found anywhere in distribution
	writing manifest file 'pandas.egg-info\SOURCES.txt'
	running build_ext
	Traceback (most recent call last):
	  File "setup.py", line 740, in <module>
		**setuptools_kwargs)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\core.py", line 148, in setup
		dist.run_commands()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\dist.py", line 955, in run_commands
		self.run_command(cmd)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\dist.py", line 974, in run_command
		cmd_obj.run()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\site-packages\setuptools\command\develop.py", line 36, in run
		self.install_for_development()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\site-packages\setuptools\command\develop.py", line 134, in install_for_development
		self.run_command('build_ext')
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\cmd.py", line 313, in run_command
		self.distribution.run_command(command)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\dist.py", line 974, in run_command
		cmd_obj.run()
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\site-packages\Cython\Distutils\old_build_ext.py", line 186, in run
		_build_ext.build_ext.run(self)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\command\build_ext.py", line 308, in run
		force=self.force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\ccompiler.py", line 1031, in new_compiler
		return klass(None, dry_run, force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\cygwinccompiler.py", line 285, in __init__
		CygwinCCompiler.__init__ (self, verbose, dry_run, force)
	  File "C:\Users\MY_USER_NAME\AppData\Local\Continuum\anaconda3\envs\pandas_dev\lib\distutils\cygwinccompiler.py", line 129, in __init__
		if self.ld_version >= "2.10.90":
	TypeError: '>=' not supported between instances of 'NoneType' and 'str'


#### Expected Output

I'd love to have a nice error message which I can work with. As I have not set up any cygwin compiler and hoped that behind the scenes Visual Studio 2017 would be chosen automatically, now it is a bit difficult to guess what the real problem is unless I step through the code.

#### Output of ``pd.show_versions()``

Latest commit is [d80a4b81938e3982708ccd012e983f11aa651af1](https://github.com/pandas-dev/pandas/commit/d80a4b81938e3982708ccd012e983f11aa651af1)
