Adding common WebDriver interface for python bindings

The python bindings for the various drivers do not share a common interface, so it's hard to tell from a glance which driver implements what, or if they even use the same name for each function.  This CL defines a common interface for the WebDriver and WebElement classes to help fix this.  I've also copied over documentation from javadoc so we can generate pydoc files for our oft-neglected python users.

[simonstewart, 2010-08-03 13:47:15]

LGTM. I like the fact that there's no distinction between webelement and
renderedwebelement, though I'd be tempted to move the drag and drop methods off
there until some asks for them --- they're not quite in the right place.

[jleyba, 2010-08-03 17:17:11]

Done.

On 2010/08/03 13:47:15, simonstewart wrote:
> LGTM. I like the fact that there's no distinction between webelement and
> renderedwebelement, though I'd be tempted to move the drag and drop methods
off
> there until some asks for them --- they're not quite in the right place.