Bugfixes. Add save and load methods to symbolic_solution.
Add output file.
Remove unused module.
Don't leave open 'w'-mode files.
Bugfix
Bug fix and minor code refactoring.
Fix circular dep.
Bugfix
Merge branch 'master' of https://github.com/ahkab/ahkab into refactor

Conflicts:
	ahkab/results.py
	ahkab/symbolic.py