Changing inputfile so that it can be properly tested (not finished).
Merge branch 'my_changes' into merging_branch

Conflicts:
	abipy/htc/inputfile.py
Quick fix to remove some obsolete imports from pymatgen.
Quick fix to remove some obsolete imports from pymatgen.
Fixed representation of signed integers in the input file.
Merge pull request #14 from GkAntonius/master

Reorganized abipy.htc.inputfile