Add gdbserver to snappy image

[Hans Mayer]

To develop applications on ubuntu snappy image for beaglebone black, eclipse CDT needs a gdbserver installed and running on snappy. On "standard" ubuntu images, it is simple to gdbserver with "apt-get install gdbserver".

Thus "gdbserver" should be distributed in snappy image.

An other solution is to add a functionality "snappy import <packagename>.deb" to import existing (ubuntu desktop) applications in the same way as "sudo apt-get install ...".

Or if this is not possible, creating an ubuntu desktop application "convert debian package to snappy click package" including all package dependencies to generate automatically (!) the click package.