Merge git://git.bogomips.org/git-svn

* git://git.bogomips.org/git-svn: Document git-svn's first-parent rule git svn: attempt to create empty dirs on clone+rebase git svn: add authorsfile test case for ~/.gitconfig git svn: read global+system config for clone+init git svn: handle SVN merges from revisions past the tip of the branch