Update README.md

Added build status image
Moved files into lib subdir

Signed-off-by: Michael Greenhill <doctorjbeam@gmail.com>
Moved composer files back to root

Signed-off-by: Michael Greenhill <doctorjbeam@gmail.com>
Alterations for Travis CI and PHPUnit test

Signed-off-by: Michael Greenhill <doctorjbeam@gmail.com>