New Year cleaning #5: nix Analytics and RegExp.

Analytics was only ever implemented on the HTML5 backend and was never going to
be implemented meaningfully on any other backend.

RegularExpression was Java's regexp on Java/Android and HTML's regexp on HTML5,
which are incompatible. Better to leave games to fend for themselves (and do
things safely in a per-platform manner) than to pretend that a cross-platform
API for something as complex as regexps could possibly exist.

If you need consistent cross platform behavior, bundle a pure Java regexp
library with your game. If you need high performance, implement exactly what
you need, tweaked specifically to work for HTML's regexps and Java's regexps in
your own per-backend code. Or if you never plan to run your game in HTML5, then
just use java.util.regex.Pattern directly.

In theory these should have gone through a deprecation cycle, but they're both
so half-assed that no one could possibly have been seriously relying on them.