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
Maybe if we revert the columns with the rows, it'll look like a timeline?

| ver     | 3.2.3                                                                                                                                  | 3.3.x                                                                                                                                  | 3.4                                                                                                                                    |
|---------|----------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------|
| Stable  | [![Build Status - 3.2/master](https://travis-ci.org/kohana/unittest.svg?branch=3.2%2Fmaster)](https://travis-ci.org/kohana/unittest)   | [![Build Status - 3.3/master](https://travis-ci.org/kohana/unittest.svg?branch=3.3%2Fmaster)](https://travis-ci.org/kohana/unittest)   |                                                                                                                                        |
| Develop |                                                                                                                                        | [![Build Status - 3.3/develop](https://travis-ci.org/kohana/unittest.svg?branch=3.3%2Fdevelop)](https://travis-ci.org/kohana/unittest) | [![Build Status - 3.4/develop](https://travis-ci.org/kohana/unittest.svg?branch=3.4%2Fdevelop)](https://travis-ci.org/kohana/unittest) |