#972620 by dereine: Add an administrative title field for all handlers to make it more possible to distinguish similar fields from each other in the UI.

#477984 by demeritcowboy, fatstar415, mike dodd, dagmar: Properly handle value for "empty" and "not empty" special operators.

#653628 by dagmar and dereine: Ensure child method declarations match parent method declarations to prevent notices.

#652716 by dagmar: "no single" flag on filter objects not completely respected, causing improper default filters.

Clean up admin.inc because it had invalid line endings
Fix a notice when using ajax and pagers
Fix use_ajax which had lost its submit handler and could not be changed

Major re-organization of handlers. PLEASE NOTE: This drastically affected the Views module API and until modules are updated to match, they will stop working. Efforts have been made to ensure that this won't cause your site to crash, but that's partly up to the individual module as well.