Remove obsolete text assignment; other code improvements

- text assigned by Page.get() is never used
- cosmetic_changes are disabled by
  config.cosmetic_changes_deny_script list object
- remove obsolete "global" declaration for bot object

Change-Id: Ifdd9f5e74f58d8258ad4bb62986ed9a18b6aeeff
Merge "Remove obsolete text assignment; other code improvements"