TEST: add tran1, test all tran methods.
Merge branch 'master' of https://github.com/ahkab/ahkab into tests
DOC: improvements.
Much faster implementation of set_submatrix
Use linalg to solve, speed up considerable.
Allow solving with sparse matrices. (speed up)
DOC: improvements
Merge branch 'master' of https://github.com/ahkab/ahkab into tests
Add print_model()
Merge branch 'master' of https://github.com/ahkab/ahkab into tests
TEST: add test for BFPSS
Merge branch 'tests' of https://github.com/ahkab/ahkab into py3

Conflicts:
	ahkab/bfpss.py
PY3: print
TEST: bfpss1 fix ref extension, add isource
TEST: add shooting test shooting1
Merge branch 'tests' of https://github.com/ahkab/ahkab into py3