X11 headers and libraries are only required if we're actually using X11
which may not be the case.
This allows to build wxGTK on the systems using Wayland-only GTK.
Build the cotire test project and check if it succeeds. Also check if the
'had text segment at different address' warning does not appear in the build
output. If it does not succeed, disable usage of precompiled headers.
If the PCH option was changed, clean the project and rebuild it again. Do not
clean everytime the project is configured because (re)building the cotire test
project takes some time.
Support checking for multiple versions, first check gstreamer-1.0, then gstreamer-0.10.
Add support for finding gstreamer-player.
Specify the required components, add the include directories and link with the libraries of the found components.
Set the setup variables wxUSE_GSTREAMER and wxUSE_GSTREAMER_PLAYER.
Add CMake-based build system.
Merge the original branch without any changes except for resolving the
conflict due to moving the contents of .travis.yml to a separate file by
propagating the changes done in this file since then to the new script
and rerunning ./build/update-setup-h and ./build/cmake/update_files.py
to update the file lists changed in the meanwhile.
Closes https://github.com/wxWidgets/wxWidgets/pull/330
Add CMake build system for libraries, tests and samples
update_files.py converts build/files into CMake format.
build/update-setup-h has been modified to update build/cmake/setup.h.in.