CLN: ASV replace
- Flake8'd and removed star imports

For the `ReplaceDict` benchmark I reduced the number of samples from 10^6 to 10^5 because it was taking a significant amount of time, but 10^5 samples should still be representative of a large sample performance.

```
asv dev -b ^replace
· Discovering benchmarks
· Running 4 total benchmarks (1 commits * 1 environments * 4 benchmarks)
[  0.00%] ·· Building for existing-py_home_matt_anaconda_envs_pandas_dev_bin_python
[  0.00%] ·· Benchmarking existing-py_home_matt_anaconda_envs_pandas_dev_bin_python
[ 25.00%] ··· Running replace.Convert.time_replace                                                               ok
[ 25.00%] ···· 
               ============ =========== ===========
               --                 replace_data     
               ------------ -----------------------
                contructor   Timestamp   Timedelta 
               ============ =========== ===========
                DataFrame      411ms       409ms   
                  Series       349ms       349ms   
               ============ =========== ===========

[ 50.00%] ··· Running replace.NaN.time_fillna                                                                    ok
[ 50.00%] ···· 
               ========= ========
                inplace          
               --------- --------
                  True    6.42ms 
                 False    15.0ms 
               ========= ========

[ 75.00%] ··· Running replace.NaN.time_replace                                                                   ok
[ 75.00%] ···· 
               ========= ========
                inplace          
               --------- --------
                  True    7.09ms 
                 False    23.6ms 
               ========= ========

[100.00%] ··· Running replace.ReplaceDict.time_replace_series                                                    ok
[100.00%] ···· 
               ========= =======
                inplace         
               --------- -------
                  True    7.43s 
                 False    7.48s 
               ========= =======
```