test: remove getAppPath test in UtilLinux_test

this function will be tested by "GUI" Test cases as well.

If it's working desurium will start correctly, if not then not.
It doesn't make sense to test this function the same way it was implemented.
partially revert "Travis:"

the update of all needed package can fail unter some circumstances.
See here: https://travis-ci.org/karolherbst/Desurium/builds/4325989

We should install only the missing ones
Merge pull request #413 from karolherbst/bug392

test: remove getAppPath test in UtilLinux_test
Merge pull request #414 from karolherbst/travis

partially revert "Travis:"