gitstat update

Helptext update and test suite added.

wttr update

Added test suite.

wttr incorrectly advertised support for -V as the short form of
--version.

vimsplit update

Test suite added.

Error messages were being incorrectly suppressed.

Test updates

Added two minor tests for ctdir

Added test suite for enumerate

Rewrote tests with bats

As evidenced by the 11 prior commits, proper testing has revealed a
large number of gaps and inconsistencies in these scripts. bats is a
very capable replacement for the old test suite.