git package redistrubutes some Microsoft copyrighted files + git post install script partially fails + bash stdin stdout files test fails

* This git package redistrubutes some Microsoft copyrighted files. This happen because of the git post install script (that should be run on user machine only!) copying some Windows files.
* Git post install script invoked the wrong way. The file says that it should be:
```bat
git-bash.exe --no-needs-console --hide --no-cd --command=post-install.bat
```
* But fixing it doesn's fix some unknown errors in the post install script. So that conda build fails if used this way:
```bat
git-bash.exe --no-needs-console --hide --no-cd --command=post-install.bat || exit 1
```
or this way:
```bat
call post-install.bat || exit 1
```

Actually this package does redistribution the wrong way. The right way is to do literally the same as original git devs intended. So I suggest go with [no_link](https://conda.io/projects/conda-build/en/latest/source/resources/define-metadata.html#no-link) and run post-install on the user machine.