exercises/02: Fix shaders to produce a link error, not a compile error
waffle: Add cmake flags for manpages and htmldocs

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Make project work with older versions of clang.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Solution to exercise 1.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Refactoring (currently doesn't work).

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>