The default merge_file level was XDL_MERGE_MINIMAL, which will
produce conflicts where there should not be in the case where
both sides were changed identically.  Change the defaults to be
more aggressive (XDL_MERGE_ZEALOUS) which will more aggressively
compress non-conflicts.  This matches git.git's defaults.

Increase testing around reverting a previously reverted commit to
illustrate this problem.

"Uninitialized" submodules are "unmodified"

Extend the "unmodified" submodule workdir test to include
uninitialized submodules, to prevent reporting submodules as
modified when they're not in the workdir at all.

git_reflog_entry_message can be null

Fix a couple of corner cases and an undefined behavior

Fix segfault when calling git_config_get_* functions when a config fails to load

Reinitialize the result code of get_entry() to GIT_ENOTFOUND

Convert gitdir paths to posix on Windows

Apparently, a .git file with "gitdir: path" link on Windows is
allowed to use backslashes in the path.  Who knew?

Fix some documentation issues.

Run Coverity scan on Travis

Update README to include Java, PowerShell bindings

refs: remove the _with_log differentiation

Any well-behaved program should write a descriptive message to the
reflog whenever it updates a reference. Let's make this more prominent
by removing the version without the reflog parameters.

Common

Align `*_dup` functions

Implement @cmn's suggestions for `git_remote_dup`.

This changes git_signature_dup to actually honor oom conditions raised by
the call to git__strdup. It also aligns it with the error code return
pattern used everywhere else.

Add `git_remote_dup`.

Fix a bunch of memory leaks.

Stream packs to the destination