Multiple report types, compatibility with ash and pdksh

pdksh does not support $.sh.file so a quick check was added.

Functions for modular report types were added. testsuite_run now
display tests as dots, testsuite_spec displays as a list.

Improvements on zsh stack trace to use only the basename of the
file on each trace line.
Trying out a travis job

Commiting a .travis.yml is required for the first try-out on
travis-ci.org. Subsequent commits may be needed for fixing the
configuration parameters and adding the badge to the README