Fswatch

* Issue 218: fswatch v1.13 ignores the --monitor parameter and always uses the
default monitor.

* Issue 178: Migrate usages of POSIX regular expressions (<regex.h>) to the
C++11 regex library (<regex>).

* Issue 191: Wrong error message is printed when inotify event queue overflows.

* Issue 192: Make the build reproducible.

* Issue 182: Generate a single message catalog for both fswatch and
libfswatch.

* NLS support can be disabled.

* gettext is an optional dependency.

* Issue 182: Remove mandatory dependency to git.

* Issue 174: Allow a numeric event mask to be specified.

* Issue 181: Make gettext an optional dependency.