Add an ignoreError flag to the DVcsJob class.

This allows ignoring non-zero exit codes and treat the Job as though
it completed successfully. This is useful if the output of the Job
already contains sufficient information so that handling a special
error code is no longer necessary.
Change the command to get the current branch name for git.

"git sumbolic-ref" also provides a valid branch name when the
repository is empty. In detached HEAD state it has an empty
output, which is exactly what we did before manually. However,
in that case it also returns with a non-zero exit code which
we need to ignore.

REVIEW: 115121
Kill Kross integration - it isn't working since ages and with the move to KF5 it becomes obsolete anyways.
Remove dead code and clang warnings.
Revert showing diffs on left-clicking the annotation bar; use menu instead

There's already a context menu to show the diff, that it was not shown
when the action was invoked via the shortcut was a bug which is now fixed.
Generate proper path here
Make global data static const.
Enable the intializer_list for Clang - it's supporting it.

Qt4 is lacking in that regard. While at it, also make use of that
feature for the output filtering strategies.
Cleanup code and output actual values in a nice way.
To properly classify the automoc line we must match the whole line.

This fixes the test for me locally.
Fixup enabling of initializer lists