We _dispose_ the contents of objects; we _free_ objects (and their
contents).  Update `git_strarray_free` to be `git_strarray_dispose`.
`git_strarray_free` remains as a deprecated proxy function.

The code worked under the assumption that anything under `refs/tags` are
tag objects, and all the rest would be peelable to a commit. As it is
completely valid to have tags to blobs under a non `refs/tags` ref, this
would cause failures when trying to peel a tag to a commit.

Fix the broken filtering by switching to `git_revwalk_push_glob`, which
already handles this case.

Since libssh2 doesn't read host configuration from the config file,
this callback can be used to hand over URL resolving to the client
without touching the SSH implementation itself.

Move to the `git_error` name in the internal API for error-related
functions.

A newly added test uses the `git_repository_new` function without the
corresponding header file being included. While this works due to the
compiler deducing the correct function signature, we should obviously
just include the function's declaration file.

Given a wholly in-memory repository, ensure that we can create an
anonymous remote and perform actions on it.