Add git_branch_name()

This is a convenience function to get the branch name of a given
ref. The returned branch name is compatible with the name that can
be supplied e.g. to git_branch_lookup(). That is, the prefixes
"refs/heads" or "refs/remotes" are omitted.

Also added a new test for testing the new function.

The index is empty; repeated tree entries cannot collide.

cc github/gitrpc#83

Update remote tips on push

update examples to work on windows

Don't clear the opt instance in the diff example.

The version field is overwritten otherwise. The opt instance is
already initialized properly.

Global options setter

Allow peeled references without trailing newline at end of file

as per @vmg's request

Also ammends one of the tag tests to make sure it's working.

Fix case sensitivity bug with tree iterators

With the new code to make tree iterators support ignore_case,
there is a bug in setting the start entry for range bounded
iterators where memcmp was being used instead of strncasecmp.
This fixes that and expands the tree iterator test to cover
the cases that were broken.

This reverts commit 28b1cdf3.

//cc #1262 #1267

A simple perf optimization in pack-objects.c

Handle packed peeled objects without trailing newlines

Fixes #1262

Update clar to a80e7f30

Parse commit time as uint64_t to avoid overflow

The commit time is already stored as a git_time_t, but we were
parsing is as a uint32_t.  This just switches the parser to use
uint64_t which will handle dates further in the future (and adds
some tests of those future dates).

When the encoding header changed to be treated as an additional
header, the EOL pointer started to point to the byte after the LF,
making the git__strndup call copy the LF into the value.

Increase the EOL pointer value after copying the data to keep the rest
of the semantics but avoid copying LF.

Fix really bad error handling in git_smart__negotiate_fetch

Fix linking error caused by ddcb28a4.

add an index_remove_bypath that removes conflicts

Move all non-ascii test data to raw hex

add a git config, don't run crlf tests on non-win32