Added changes list caching so that changes wouldn't be downloaded multiple times if Changes property queried more then once.
Added changes list caching so that changes wouldn't be downloaded multiple times if Changes property queried more then once.

codemerlin/git-tfs,kgybels/git-tfs,steveandpeggyb/Public,PKRoma/git-tfs,vzabavnov/git-tfs,NathanLBCooper/git-tfs,TheoAndersen/git-tfs,spraints/git-tfs,kgybels/git-tfs,bleissem/git-tfs,adbre/git-tfs,jeremy-sylvis-tmg/git-tfs,adbre/git-tfs,WolfVR/git-tfs,allansson/git-tfs,timotei/git-tfs,bleissem/git-tfs,modulexcite/git-tfs,spraints/git-tfs,irontoby/git-tfs,modulexcite/git-tfs,jeremy-sylvis-tmg/git-tfs,hazzik/git-tfs,jeremy-sylvis-tmg/git-tfs,git-tfs/git-tfs,hazzik/git-tfs,hazzik/git-tfs,timotei/git-tfs,steveandpeggyb/Public,adbre/git-tfs,allansson/git-tfs,codemerlin/git-tfs,codemerlin/git-tfs,hazzik/git-tfs,andyrooger/git-tfs,spraints/git-tfs,WolfVR/git-tfs,WolfVR/git-tfs,TheoAndersen/git-tfs,kgybels/git-tfs,timotei/git-tfs,guyboltonking/git-tfs,TheoAndersen/git-tfs,NathanLBCooper/git-tfs,guyboltonking/git-tfs,irontoby/git-tfs,TheoAndersen/git-tfs,irontoby/git-tfs,guyboltonking/git-tfs,NathanLBCooper/git-tfs,allansson/git-tfs,allansson/git-tfs,bleissem/git-tfs,modulexcite/git-tfs,steveandpeggyb/Public,pmiossec/git-tfs