Made the following changes
1] Added ode_1st_power_series for first order differential equations
Merge branch 'master' into seriessolve

Conflicts:
	sympy/solvers/deutils.py
	sympy/solvers/ode.py
	sympy/solvers/tests/test_ode.py
Made following changes
1] Moved boundary conditions out of power series classification
2] Rectified test failures
3] Added doctest
4] Removed power series out of best hint
Added order term
Changed:
1] Minor whitespace error
2] Modified power_series hint such that doctest does not hang
Modified:
1] Moved power series above lie_group
2] Minor bug in lie_heuristics
Corrected minor bug in Order
Power series solution for 2nd order eqns at ordinary points
Made following changes:
1] Added docstring tests
2] Fixed test failures
Minor changes
1] Fixed a bug (removed factorial)
2] Added a few more tests
Added support for solving 2nd order diff eqns at reg points
Made the following changes
1] Added doctests and tests
2] Changed the max limit such that it is congruent with
   series
3] Rectified test failures
Changed n to int(n)
Merge pull request #2395 from Manoj-Kumar-S/seriessolve

SeriesSolve support for SymPy