AST, Type: Nodes now sport line info.

Conflicts:
	compiler/type.py
Parser: Decorate AST/Type nodes with line info.

Conflicts:
	compiler/parse.py
Parser: Refactor lexpos initialization from first token.

Conflicts:
	compiler/parse.py
Type: Add line info to error messages.
Type: On constructor reuse error, show previous definition.
Parser, AST, Type: Refactor lexpos initialization from another node.

Conflicts:
	compiler/type.py
Parser: Beautify line tracking; drop tracking of Program node.
Merge pull request #23 from Renelvon/lineinfo2

Add line tracking to parser. Add line info to errors of type module.