Initial Travis support. Still needs proper setup.
[Travis] Install qt4 and set qmake_executable variable.
[Travis] Install ITK and DCMTK and enable more CTK options.
Fixed ITK dir and ctest upload.
[Travis] ITK fix.
[Travis] Install gdcm dependency.
Add virtual X server support to travis

This should provide an xserver that will allow the
Qt and VTK tests to pass.

Follow method used here:

https://github.com/archSeer/glu/blob/master/.travis.yml
Merge branch 'travis-Xdummy'

Conflicts:
	.travis.yml