Update symmetry.py

Function location has changed in latest version of pymatgen.
Merge pull request #42 from GkAntonius/patch-4

Update symmetry.py
Fix import error
Deprecated classes
Merge branch 'master' of https://github.com/gmatteo/abipy

Conflicts:
	abipy/fworks/abifw.py
Remove deprecrated objects
More Py3k fixes
Use silicon as test for raman_optic
Merge branch 'master' of https://github.com/gmatteo/abipy
fix import
Merge pull request #43 from gpetretto/fixes

fix import
Use pprint_table from monty
Merge branch 'master' of https://github.com/gmatteo/abipy

Conflicts:
	abipy/tools/text.py
Bug in run_raman_optic
Merge branch 'master' of https://github.com/gmatteo/abipy
Merge pull request #44 from yanikou19/master

Use silicon instead of BiFeO3 for run_raman
Merge branch 'master' of https://github.com/gmatteo/abipy
Add natfix to abinit_vars.json
Fix docs
Improve docs