This namespace is about behaving like git's branch command, so let's do
exactly that instead of taking a reflog message.
This override is still available via the reference namespace.
The signature for the reflog is not something which changes
dynamically. Almost all uses will be NULL, since we want for the
repository's default identity to be used, making it noise.
In order to allow for changing the identity, we instead provide
git_repository_set_ident() and git_repository_ident() which allow a user
to override the choice of signature.
This adds another assertion to ensure that the reference name inside
the git_reference struct returned by `git_branch_create` is returned as
precomposed if `core.precomposeunicode` is enabled.
Only on a filesystem that is composed/decomposed insensitive,
should be testing that a branch can be looked up by the opposite
form and still work correctly.
When using Iconv to convert unicode data and iconv doesn't like
the source data (because it thinks that it's not actual UTF-8),
instead of stopping the operation, just use the unconverted data.
This will generally do the right thing on the filesystem, since
that is the source of the non-UTF-8 path data anyhow.
This adds some tests for creating and looking up branches with
messy Unicode names. Also, this takes the helper function that
was previously internal to `git_repository_init` and makes it
into `git_path_does_fs_decompose_unicode` which is a useful in
tests to understand what the expected results should be.
