TeXCHR Is Born!

Basic FreeCHR semantics, see the README.md for details on this release!

We can define and run fibonacci:

\chr{fib test}{
   \LimitCycles{25}
   \Compose{
      \Rule{main}{}{{\true}}{\true}
      {
         \tuple{\c{0}}
         \add{\fst}{\snd}
         \ebody{\snd:\res}
      }
   }
   \Run{{0:1}}
}