Added a sample that fixes comment two on issue #1264.
Added .H and .C as C file extensions as well as them already being C++ ones. This fixes #1054
Added the GLKit GLKMatrix4 header as a C sample as this fixes 5 misclassifications - 4 as Obj-C and one as C++
Added C header samples from https://github.com/MiJyn/nightmare/ to fix the misclassifications as C++ that were occuring