LibGit2Sharp v0.12.0 发布，libgit2的.Net封装

LibGit2Sharp支持libgit2（一个原生Git实现）拥有的所有功能和速度。用于管理.Net和Mono项目。

Release Notes: This release added repo.Info.IsShallow and repo.ObjectDatabase.CreateTag(). repo.Reset can now append to the Reflog. repo.Diff.Compare() is now able to define the expected number of context and interhunk lines. TreeEntryTargetType.Tag is now obsolete. libgit2 binaries were upgraded to libgit2/libgit2@9d9fff3. The probing mechanism was changed to rely on specifically named versions of libgit2 binaries. Two versions of LibGit2Sharp can now run side by side