[INTERNAL] Adds class to load swt libraries

This is another commit to prepare the introduction of
the SWT browser. The SWT libraries of the SWT plugin
can now be loaded from the Intellij plugin.

Change-Id: I8dd81e8a0e7f9a9aa452a2716ad4a767cc5d0bff
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/2029
Tested-by: Jenkins CI
Reviewed-by: Holger Schmeisky <google@schmeisky.com>