Fixes #33 - commit messages needs to be escaped

Adds status info to commit details quick pick

Changes Show Previous Commit History to Show Previous File History

Adds clipboard copy message to commit files quick pick list

Now shows the previous commit details

Clears broken blame on close

Adds Open File command to commit quick pick

Executes showQuickRepoHistory if there is no active editor

Copies the sha of the most recent commit to the repository if there is no active editor

Adds copyMessageToClipboard to the editor content menu
Adds copyMessageToClipboard to showQuickCommitDetails quick pick

Show commands rather than file set

Adds showQuickRepoHistory command to CodeLens
Adds showQuickCommitDetails command to the status bar
Adds showQuickRepoHistory command to the status bar
Changes recent CodeLens default command to showQuickCommitDetails
Changes status bar default command to showQuickCommitDetails

So that it can hide/restore the hover blame annotation if needed