Merge branch 'master' into development
Updated Makefile.

Now pulls .o and .obj files from libglfw3.a.
Add CMAKEFLAGS environment variable to LIBGLFW build.
GLFW is now built within BUILD/GLFW.
Fixed sge_depends issues.

Works around Window’s Rectangle function (automatically included from
gl.h).
Quoted error message to silence GCC warnings.
Added Wno-unknown-pragmas to CXXFLAGS

Silences GCC warnings.
Merged PR#4