Use [].indexOf shim on IE<=8

where [].indexOf is not implemented
Make typeable test compatible with IE<=8

[].indexOf is not defined on IE<=8
fix typeable
fix typeable test
old IE support: Replace element.focus with Syn.__tryFocus()

element.focus() will throw in old IE if the element is invisible or
under other conditions.
Remove extra trailing spaces in mouse.support.js
Rebuild Syn