Added Sys.UI.DomElement definitions and tests.
Added Sys.UI.Point definitions and tests.

Fixed minor definitions with some overrides.
Fixed PageRequestManager event handlers and definitions to take in the correct EventArgs type.
Corrected tests to reflect the definitions.
Added arg definition methods to the event handlers in the Tests for PageRequestManager.
Fixed definition issue where PageRequestManager extends from EventArgs which is invalid.
Added Sys.UI.DomEvent definitions and tests.
Made some tests have Explicitly typed variables to see immediately the returning type.
Merge branch 'master' of https://github.com/borisyankov/DefinitelyTyped
Merge pull request #2270 from pjmagee/master

Added Sys.UI.DomElement definitions and tests to microsoft-ajax