Add stats CLI option.

[belav]

This output was printing all the time. Lets put it behind a option and clean it up.

total time:                                                                          225ms
Total files:                                                                           1
Failed syntax tree validation:                                                         0
Threw exceptions while formatting:                                                     0
files that threw exceptions while validating syntax tree:                              0

[belav]

see CommandLineFormatter line 129 or so

[belav]

let's not