Add standalone build for 3.4 series

Merges the 3.3/develop branch up to 3.4/develop and updates the travis and composer configs for 3.4.x - continues kohana/kohana#50
> People who are already using 3.2 know the support and build status, and we're surely not suggesting anyone who finds Kohana now bothers to look at it?

Yeah! I guess you're right. It will be even more confusing :)