Pharcc integration

As discussed in #131, this is an integration of phpcc as build-tool. The build-process itself has not changed. Following would be sufficient:

```
git clone ...
cd phpbrew
composer install
./scripts/compile
```

And after that the phpbrew binary is there. But there is one disadvantage: The binary is slightly bigger than the old one. Around ~15% - i don't exactly know why, but i think for a dev-tool < 100k is still okay