Rename command names to be compatible with Symfony commands?

[fprochazka]

Question raised by @foxycode in #247

If we do this, there should be an (by default turned off?) option for backward compatibility aliases.

[foxycode]

@fprochazka Since you are releasing new major version, why? :-)

[fprochazka]

Major version = opportunity to break things != neccesarity to break all the things.
Easing the transition is always a good thing :)

[foxycode]

@fprochazka No problem, I can add old aliases if you like. I think I reather finish previous console related issues before this one.

[fprochazka]

@foxycode let's take small steps :) that's always better