Log Message:
Update to 0.4.0:

Release 0.4.0 (2014-10-15)
==========================

- Corrected return value documentation for xcb_image_shm_put().
- Added additional format tests for XY_PIXMAP bit planes.
- Changed test_xcb_image to work with XY_PIXMAP with nontrivial planemask.
- Fixed get_image to handle xy format with nontrivial plane_mask.
- Fixed endianness bug in xy pixmap getimage.
- Use AC_CONFIG_HEADERS to create a config.h file.
- Add missing COPYING file.
- Using X11 Protocol headers, so XPROTO_CFLAGS is required.
- Move test cases into their own directory.
- Fix compilation when NDEBUG is defined.