Revert "alternative implementation of DLX using arrays of integers"

This reverts commit 225d920443df3a2b3860ba5e532957f3794c4478.
Revert "remove meta (auto generated by ocp)"

This reverts commit f978e1210bc07707169abc2c4cc7c11bbf77b4bb.
Revert "clean Makefile"

This reverts commit fc006be0c0643e2b3e1b62776f95ad374d0e4b6f.
Revert "move all src files in src root"

This reverts commit f1fb933e3185212fceb065f80b5194a975a8962b.
Revert "re-add Makefile"

This reverts commit 4f5e17ea1caaca88f8f95a3ad7b5f496c2f741a9.
Revert "move + remove color from ocp"

This reverts commit 7b3d73760807a978783a225e3d4da9cf5f0d82b1.
Revert "move files"

This reverts commit 01408acb80d8f2ee6ccf843b20f514cb8533ee93.
Revert "switch build system to ocp-build"

This reverts commit ef3cc5157b84f63dc230d4f100f7b67aefa4c6e0.
revert commits before ocp-build with last commit