No longer need to be in 'tests' directory

Your BASH version is checked; if it's 3, you will have to ignore this
commit, unfortunately. To be fair, if you're on 3 (major), you have
more pressing matters. :P

tests/lenchk

@@ -95,6 +95,10 @@ while [ "$1" ]; do
 	shift
 done
 
+# Thank you, Chubin. Feature apparently added in version 3.0 alpha, so should
+# be OK, but if anyone is having issues, just `cd` to the 'tests' directory.
+[ ${BASH_VERSINFO[0]:-0} -eq 3 ] || cd "${BASH_SOURCE[0]%/*}"
+
 # Confirm we are in the right place.
 git rev-parse --is-inside-work-tree 1> /dev/null 2>&1 ||
 	Err 0 'Not inside a Git repository.'