1. Added note querying method to dbmanager.
2. refined layout in sslist, sslistitem, historyview, historyviewdetails
3. added listener to stats button in historyListActivity and historyview
4. created Stats class for calculation of stats.
5. added statsDialog in HistoryListActivity to show stats.
6. modified EditNoteActivity to handle note view (editing disabled)
7. added time, date and duration fields in StudySpace, DBManager for
stats. (not used yet).
Merge branch 'master' of github.com:jywu/StudySpace

* 'master' of github.com:jywu/StudySpace:
  add note edition in history details page

Conflicts:
	src/edu/upenn/cis573/EditNoteActivity.java
	src/edu/upenn/cis573/HistoryListActivity.java