Fix #2320
Add a (default) CI_DB_query_builder::_update_batch() method

An improved version of PR #2324, which only targets ODBC.
Output Class Minify Function Change

Added 2 additional MIME types to match against for JavaScript detection.
adding thumb_marker to image_lib->clear()
removing linebreak
Merge pull request #2326 from bayssmekanique/develop

Output Class Minify Function Change
Merge pull request #2328 from samdoidge/develop

adding thumb_marker to image_lib->clear()