Prevent crashes regarding modal dialogs and dangling pointers

We need to use QPointer, as pointed out by the krazy2 analysis tool.
Make constructors of widgets explicit to avoid conversion construction
Fixed typos pointed out by krazy2 analysis tool
String related performance optimizations pointed out by krazy2 analysis tool
Use normalized SIGNAL SLOT signatures
Merge branch 'v0-8'

Conflicts:
	include/SaveAsRPMDialog.h
	include/TailoringWindow.h
	src/SaveAsRPMDialog.cpp
	src/TailoringWindow.cpp