Currently, the ScintillaObject signals can't be used from python code via
gobject-introspection. This is because g-ir-scanner does not properly scan
the signals.

For signals, there is the additional requirement that parameters have are
registered GTypes. For the sci-notify signal, this can be accomplished by
boxing SCNotification.

In addition, g-ir-scanner also runs on Scintilla.h where it picks up
additional structs.

test/gi/ is updated accordingly. The test python script is enhanced
to showcase the signals (some fixes to the makefile are included as well).

Currently, the ScintillaObject signals can't be used from python code via
gobject-introspection. This is because g-ir-scanner does not properly scan
the signals.

For signals, there is the additional requirement that parameters have are
registered GTypes. For the sci-notify signal, this can be accomplished by
boxing SCNotification.

In addition, g-ir-scanner also runs on Scintilla.h where it picks up
additional structs.

test/gi/ is updated accordingly. The test python script is enhanced
to showcase the signals (some fixes to the makefile are included as well).

Avoid doc-comment in header as they are interpreted by g-ir-scanner, fix a typo,
remove empty lines, add to change log.

- remove any notion of deprecation of legacy symbol names
- make sure typelib search path is set for test program
- add separate test target to test/gi/makefile
- improve g-ir-scanner call command line
- fixed gtk2 support of test test/gi/gi-test.py

The test suite acts also as an example for downstream projects to generate
gobject-introspection data. A known-good .gir file is checked in for checking
results in the future. Lastly, a small python uses the gobject-introspection
data to create a small editor window.

The change to gtk/makefile is because scintilla needs to be in a shared library
for the python program. Therefore scintilla.a has to be compiled with -fPIC.