changes between 2.2.7 and 2.3.3 for backporting

[dirk-thomas]

The following list of changes has been integrated into rospack 2.3.3 (Kinetic / Jade) since the last Indigo release (2.2.7).

Backported:

• backport all items listed in #71 to indigo-devel as well

Not backported:

• GNU/Hurd specific changes #64

  • no need to backport

• parsing license information #66

  • new feature, not exposed, no need to backport