Packaging/installation cleanups

1) Changes to init.d template and startup bash script to make everything
work and not spew text to the terminal
2) Startup script tries to automatically set MANTIDPATH if it hasn't been set.
3) Bumped the version number to 0.7Beta
4) Main code optionally writes a pid file (useful for the init.d script to
check)
5) Main code traps SIGTERM signals and exits gracefully