added methods to LYRA lightcurve object for extracting LYTAF information during timerange of object
updated new lyra lightcurve methods and changed method names.
updated comments in lyra.py file
restructured LYRA utilities to be outside of the lyra lightcurve class.
changed download function to use sunpy.net.download and lengthened variable names for clarity.
created a lyra.py file in sunpy/instr/ and transferred LYTAF routines to there from sunpy/lightcurve/sources/
changed output of get_lytaf_events from a list of lists to a list of dictionaries
small bug fix for returning LYTAF event string descriptor
typo fix in creating LYTAF event dictionary
removed un-needed dependency
Merge pull request #633 from aringlis/master

Added LYRA time series utilities for downloading and parsing the LYRA Timeline Annotation File (LYTAF)