Upgrade the RUbioSeq-GUI launching script

Upgrade the RUbioSeq-GUI launching script to:
- Avoid problems if it is deployed from a non-writable directory. Now,
the working dir is located at "${home}/.local/share/rubioseq-gui" (here,
the "data" folder with the database data is created).
- Add absolute routes to jetty-runner jar and rubioseq-gui*.war so that
the script can be called globally.