Replace build scripts with CMake

Rebuilding everything each time was getting a bit slow.

lib/CMakeLists.txt

@@ -0,0 +1,9 @@
+add_library(lib
+  construct.c
+  desugar.c
+  fsa.c
+  parse.c
+  regex.c
+)
+set_default_target_options(lib)
+target_include_directories(lib PUBLIC include)