Add RubyInstaller VTune build override sample.
user
```ruby
# file: <RUBYINSTALLER_ROOT>/override/vtune_build.rb
if ENV['VTUNE_BUILD'] then
  puts '[INFO] Overriding to enable VTune profiled Ruby 1.9.x...'

  RubyInstaller::Ruby19.configure_options << "--enable-vtune"
  RubyInstaller::Ruby19.configure_options << "CPPFLAGS='-Ic:/devlibs/vtune/include'"
  RubyInstaller::Ruby19.configure_options << "LDFLAGS='-Lc:/devlibs/vtune/lib32'"
end
```
assistant