augmented the set of returned values from course/session-lm query functions for the calendar feed event details. streamlined SQL queries and provided proper code docs while at it.
refactored LM flattening method out into its own helper method.
differentiated between weblink, citation and file LMs
appended notes to LM output if present and public.
added citation LM content to output.
excluded draft-status learning materials.
fixed UTC offset for ILMs in calendar feed. this time for real.
Merge pull request #345 from stopfstedt/fix_lms_in_calendar_feed

Fix lms in calendar feed