Drop geometry types support

[foxycode]

Related to #238

[fprochazka]

If anyone was using these, I encourage you to copy the code (or write better) and create your own package, because they will be removed in v4.0.
And if you're going to do that, I encourage you to make the package framework-independent.

[fprochazka]

@foxycode thank you

[fprochazka]

FYI, this looks really good on first look: https://github.com/creof/doctrine2-spatial

[foxycode]

@fprochazka What about that enum type? Shouldn't we drop it too? There sure are independent packages with doctrine types, I use oro/doctrine-extensions which doesn't have enum, but we can surely create independent type package too.

[fprochazka]

@foxycode agreed, but I don't like the current implementation. Also, using enums with mysql is pure shit, and using one enum with postgres doesn't make sense.

So it probably makes sense to drop the enum too.