Implement AbstractWindowedCursor#getType.

Additionally, update AbstractWindowedCursor#getString to call toString on values that aren't null or a Clob and throw SQLiteException for byte arrays.
These changes enable DatabaseUtils#cursorRowToContentValues to work in Robolectric tests.
Merge pull request #498 from paulblessing/cursor_to_contentvalues

Implement AbstractWindowedCursor#getType.