Lots and lots of changes
lots of changes. some (nonready) code to arithmetic encoding added.
most functions removed from headers and reloated in inline files (.i.h)
or .cpp files and explicitly instantiated in reexp.cpp. this is mainly
to improve build times.
arithmetic encoding made to work and reexpression is now encoded using
the arithmetic encoding. most function definitions moved from lang.h to
new lang.h.i in order to speed up compilation. unit tests added.
it is possible that the new relation normalization (by sorting relation
entries) eliminated some possible bugs (there was possibility that equivalence
operation failed).
cross compression now works. tests added and the expectation files are
generated for new crosscompression tests
last changes to the libreexp before publishing the paper
added missing files