Set up fake x server for Travis CI
ENH: added a few convenience methods.
ENH: maximize painting window if size larger than desktop size.
MAINT: moved old DO.Graphics test programs to `examples` folder.

Stricto sensu, this program is not a test program.
WIP: adding real unit test for `PaintingWindow` widget.
MAINT: removed javascript sample program.

This file is irrelevant.
Attempted to fix build of DO_Graphics_example.
MAINT: chmoded 644 cmake/PCH.cmake.
FIX: replaced image format `Format_RGBA888` to Format_RGB32.
Merge pull request #32 from DO-CV/maint-chmod-644-pch-cmake

[MAINT] chmoded 644 `cmake/PCH.cmake`.
WIP: adding unit tests for OpenGLWindow and GraphicsView.
MAINT: reformatted comments.
Merge pull request #31 from DO-CV/enh-add-graphics-unit-tests

[ENH] Set up GUI unit tests.
Merge remote-tracking branch 'origin' into fix-image-processing-cmake
FIX: replaced `HighResTimer` by `Timer`.

`HighResTimer` has been renamed as `Timer`.