Fitsblitz Patches

A rather big PR from the work done during the FITS Blitz project.
This includes the following changes
 - .travis.yml file for travis build.
 - Misty Demeo's performance optimisations + a small bug fix in the ant release task.
 - Gary Mcgath's Tika Enhancements
 - Gary Mcgath's update of Droid to version 6
 - Gary Mcgath's exiftool bugfixes and enhancements to the XSLTs + bugfixes
 - Gary Mcgath's bug fixes and error handling as well as logging

Some of the commits were rewritten as they incorporated different changes that we didn't want to merge (as discussed).

TBD before merging and releasing.
- Changing the FITS version in Fits.java and project.properties.
- Updating the README as discussed.