The buffer size 0 was definitely not enough so it failed

No such thing as an orphan branch

Provide libssh2 error message

Unfortunately git-core uses the term "unborn branch" and "orphan
branch" interchangeably. However, "orphan" is only really there for
the checkout command, which has the `--orphan` option so it doesn't
actually create the branch.

Branches never have parents, so the distinction of a branch with no
parents is odd to begin with. Crucially, the error messages deal with
unborn branches, so let's use that.

git_clone supports init_options

This tests the fixes for issues from #1849

Treewalker

Prevent git_tree_walk 'skip entry' callback return code from leaking through as the return value of git_tree_walk

Fix cl_assert_equal_sz error message formating

SSH: Clone fails with errors: ERROR: Repository invalid & Early EOF

errors: Fix format of some error messages

revwalk: allow simplifying by first-parent

Make odb_loose return EAMBIGUOUS when required

When enabled, only the first parent of each commit will be queued,
enabling a simple way of using first-parent simplification.

fixing headers with bad values for objective-c

fixes issues with objective-git

odb: Error when streaming in less|more bytes than declared