Mojo JS Bindings: Get rid of the module "Module" suffix

I've removed the module "Module" suffix naming convention for JS AMD
module imports. Modules are bound to a conventional name (see
below). Imported classes are bound to a const for code based on ES6
and a var for code that also runs in Chromium.

The names of imports have been regularized. The module name is just a
camel-case version of the module filename. For ".mojom" imports, a
"Mojom" suffix is added.

I did not rebind modules' exported functions. So references like
connection.bindProxyClient() or core.isHandle() still persist. The
connection functions could be added to the Connection class. I think
the core module's plethora of functions and constants would be best
left alone.

I did not revise mojo/public/js/validator.js which depends (only) on
the codec module. In that one file, the "codec." prefix doesn't hurt
readability and collisions with variables called "codec" seem very
unlikely.

BUG=
R=esprehn@chromium.org

Review URL: https://codereview.chromium.org/789763003