Merge pull request #2 from softwareradiosystems/master

Merge latest from srs
Adding info about source port name to StackDataSet.
Adding source/destination port names to StackDataSets (can be used within components)
Adding support for "above" and "below" attributes in link xml elements - can be used for stack links.
Adding Qt and Qwt support - initial work
Only including and linking qt4 & qwt if found
Qt and Qwt libs only need to be linked by launcher
Bugfix
Adding new exception
Merge pull request #4 from suttonpd/qt

Merging qt work back into main branch
Adding controller parameters (cherry-picked from andrepuschmann - thanks)
Merge pull request #5 from suttonpd/controllerparameters

Adding controller parameters (cherry-picked from andrepuschmann - thanks...)
Wrapping qt functions in QtWrapper class - allows clean exit from GUI thread event loop
Switching to use of QtWrapper in launcher, now explicitly adding header files so they get picked up by IDEs
Bugfix - need to copy ports so that new getInput/OutputDataSet calls work from template components
Bugfix - qt event thread needs to quit when exceptions are thrown
add public size() and capacity() method to StackDataBuffer
improve error message if component or command is not found
Merge pull request #8 from andrepuschmann/next_common

Two minor core changes
Merge pull request #8 from suttonpd/master

Qt support, controller parameters