Use bsdtar, to avoid installing pax droppings and failing the PLIST check.
Skip the shlib check on a plugin, on the theory that the plugin
expects the missing library to already have been loaded, and this
appears to be the case when used in qgis. Should perhaps be addressed
upstream, if someone really understands what is going on.
Qwt is an extension to the Qt GUI library from Troll Tech AS.
The Qwt library contains widgets and components which are
primarily useful for technical and scientific purposes.
It includes a 2-D plotting widget, different kinds of sliders,
and much more.
