merge class DFA with NFA and name it FiniteWordAutomaton

to be explicit, and because a DFA is a subclass of an NFA, whose proper name should minimally include "finite word", to avoid confusion (there exists enough inconsistency of terminology in the literature).

An FWA data structure does not differ (at least for now) from a BA, but their semantics are different, so better separate them.
This becomes apparent if in the future a method "to_ltl" is added to infinite-word automata.
Of course whether this should be a method or a function is another debate and since it involves interfaces, e.g.,to ltl2ba, that will live elsewhere, such a method would cause cyclic imports, so it seems appropriate that it should be a function in another tulip sub package (transys doesn't know anything about formulas).

Also, rm unimplemented is_accepted method.
rm unimplemented methods and some minor fixes
rm svg + latex export option: use tikz via dot2tex instead

latex becomes increasingly unmaintained, yields inferior results, and is confusing (and perplexes the code causing bugs).
bugfix: don't use $ on edges in tikz
bugfix: escape braces in tex
bugfix: use raw string when replacing newlines with double backslashes for tex
set nodesep and ranksep to improve space efficiency for layouts using dot
replace usage of OpenFTS with FTS
bugfix: use int actions in logic spec (worked only if Booleans used)
bugfix: the user can change the defaults env_actions, sys_actions
update tests to api changes

related to merging OpenFTS with FTS and moving sync product functions.