Add file size condition

[BrightLight]

I would like to write a condition that checks if a certain file size (or size of the overall commit?) is exceeded. For instance, people might check in large binary files, which should be recognized and blocked by the hook.

Apparently, file size cam be determined by SharpSvn:
https://stackoverflow.com/questions/14114664/how-to-get-file-size-with-sharpsvn

[BrightLight]

Might be a performance problem the way we get information of a commit at the moment (using svnlook). It would probably require to run svnlook filesize for every file that is part of the commit. Imagine you do something simple like a rename that touches a lot of files. Could be bad. Maybe we should go back to SvnSharp, which is now available also for netstandard2.0?