#90 Merge core funtionality in library

[Anonymous]

It would be nice to move core functionality into a library, so it can be used in other programming languages. This has several benefits:

* More software can take advantage of exact mathematical datatypes and functions
* GUI frontends to Maxima can make use of a library instead of a backend process, resolving any problems regarding disconnects and increasing efficiency

Note: I don't know if my idea is achievable without first porting maxima itself to a different language, and if it isn't feel free to ignore it.