config/auto/ctags - Check whether (exuberant) ctags works
Determines whether exuberant ctags exists on the system.
It is OK when it doesn't exist.
This also checks if the ctags picked up is emacs ctags which we don't want to use.
On some systems exuberant ctags is called
exuberant-ctags and on others
This test tries to work out which one we've got.
Paul Cochrane <paultcochrane at gmail dot com>