git-svn: simplify the (multi-)init methods of fetching
git-svn: simplify the (multi-)init methods of fetching

Also, some changes to avoid creating dead dirs under
.git/svn/.  We now create all directories as late as
possible.

Signed-off-by: Eric Wong <8c2951295f8292b0c03727bc4652981172298eae@yhbt.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git