big modifications to db code

you can now query for a hike with particular attributes, update a hike,
delete a hike, get the hike count, as well as all hikes in the db. more
work to be done on the query side, but it now works.
added hike query and part of results

added query functionality to the options activity. so far it searches
based on the boxes that are checked. also started on results activity.
added global data container to hold necessary classes and structures for
continued use across activities.