new H code

extrapolate H position based on C-O vector
changes
added h-position extrapolation
Cleanup

Deleted extraneous stuff and reformatted code.
parseStrands

added functionality to get Atoms by strand
Sheets

Added functionality to parse beta sheets, differentiate between parallel
and antiparallel sheets. Cleaned up code, refactored certain parts.
Merge pull request #6 from muleroid/master

Cleaned Up Stuff