Instead of using QFont's inbuilt capitalization support, which
applies only on rendering and accordingly fails for curved
labels which are drawn one character at a time, we now manually
capitalize label text while registering features.
The capitalize first method from Qt was reimplemented in QgsStringUtils
(together with what I expect is better handling of unicode characters
over the Qt method).
This change also makes it possible to implement other capitalization
methods not directly supported by Qt
Adds the ability to specify a list of text substitutes to make
which apply to label text. Eg abbrevating street types.
Users can export and import lists of substitutes to make
reuse and sharing easier.
