In test suite, factory->activity->create() should return an id, not an object

Two reasons: The value that's almost always needed is an ID, and it's more
consistent with WP's factories.

git-svn-id: https://buddypress.svn.wordpress.org/trunk@7047 cdf35c40-ae34-48e0-9cc9-0c9da1808c22
Improved sanitization in Activity component database methods

- All integer array params are filtered through wp_parse_id_list()
- Standardized LIKE clause processing

Adds tests for touched methods

Fixes #4995

Props DJPaul, johnjamesjacoby

git-svn-id: https://buddypress.svn.wordpress.org/trunk@7048 cdf35c40-ae34-48e0-9cc9-0c9da1808c22