WIP CMake Build System

[WhoBrokeTheBuild]

[dgarnier]

The current ./bootstrap is not actually working. It makes .c files from .l and .y in the source tree, but the cmake files expect them to be in the build directories. I have a branch that replaces the bison/flex part of bootstrap. I did have to make small changes to the .l and .y files though, because of the hardwiring of the output files inside those input files. See: https://github.com/dgarnier/mdsplus/tree/feature/cmake_bison_flex