Fix the call te git_commit_create in GTCommit.m which was causing the tests to break
Fix the call te git_commit_create in GTCommit.m which was causing the tests to break

When updating for the new libgit2 API this method was rewritten but the parameters for the message and message_encoding were flipped.

Turned them round the correct way and the Mac OS tests now work on master.

c9s/objective-git,0x4a616e/objective-git,TOMalley104/objective-git,misterfifths/objective-git,libgit2/objective-git,0x4a616e/objective-git,TOMalley104/objective-git,Acidburn0zzz/objective-git,pietbrauer/objective-git,Acidburn0zzz/objective-git,javiertoledo/objective-git,misterfifths/objective-git,javiertoledo/objective-git,vbergae/ObjectiveGit-Copy,alehed/objective-git,libgit2/objective-git,misterfifths/objective-git,nerdishbynature/objective-git,misterfifths/objective-git,blackpixel/objective-git,alehed/objective-git,pietbrauer/objective-git,slavikus/objective-git,c9s/objective-git,pietbrauer/objective-git,javiertoledo/objective-git,dleehr/objective-git,libgit2/objective-git,blackpixel/objective-git,dleehr/objective-git,tiennou/objective-git,0x4a616e/objective-git,tiennou/objective-git,pietbrauer/objective-git,nerdishbynature/objective-git,Acidburn0zzz/objective-git,c9s/objective-git,javiertoledo/objective-git,TOMalley104/objective-git,blackpixel/objective-git,c9s/objective-git,Acidburn0zzz/objective-git,blackpixel/objective-git,alehed/objective-git,phatblat/objective-git,royalwang/objective-git,dleehr/objective-git,libgit2/objective-git,phatblat/objective-git,slavikus/objective-git,slavikus/objective-git,tiennou/objective-git,phatblat/objective-git,dleehr/objective-git,TOMalley104/objective-git,nerdishbynature/objective-git