Refactoring and better modularization

- Reorganized code into smaller thematic modules. Most important
  internal logic refers to proto (mother of all) and relation
  objects, it is now organized in _proto and _relation folders
- Unified index logic, now both uniq index and reverse relation
  functionality is based on same indexing feature. Removed onOld/onNew
  functions
- Removed basic relation type, instead created simple which derives
  from regular relation (it was important just to simplify some of the
  behaviors instead providing a subset)
- Relation can additionally be validated via validateRelation function
- Relation set item now has it's own prototype on each relation which
  inherits from relation's prototype set item
- Cleared up set logic (one place for add/delete functionalities)
- Signal objects are now events, one for each update (no more cumulative
  updates on one signal, while it worked fine for local, it wasn't that
	friendly for imports)
- Temporarily removed import logic, as signals logic was simplified
- Objects module now provides map of all objects that are currently
  created in database
- History module separated from signal (it's still subject for
  simplification)
- Brought back function type for function only values
- Moved all utility like modules to utils folder
.. and other improvements that I forgot to describe