Build error: Fatal error: Using $this when not in object context

When building, $this is used inside a closure, causing a fatal error:

    kamermans@steve-playground:/opt/PHPCI$ php /opt/PHPCI/console phpci:run-builds
    remote: Counting objects: 228, done.
    remote: Compressing objects: 100% (147/147), done.
    remote: Total 228 (delta 127), reused 167 (delta 66)
    Receiving objects: 100% (228/228), 56.75 KiB, done.
    Resolving deltas: 100% (127/127), done.
    PHP Fatal error:  Using $this when not in object context in /opt/PHPCI/PHPCI/Builder.php on line 108
    Fatal error: Using $this when not in object context in /opt/PHPCI/PHPCI/Builder.php on line 108

The array_map/closure but was interesting, but it made it difficult to use local variables.  In particular, we need to append data to the variable $this->log, which is not accessible to the scope of the closure.  We could "use" the variable, but we would need to make a copy of it first, then copy it back to $this->log when we were finished (or experiment with explicit scalar references in a use() statement).  Anyway, I think we should just use a foreach statement here and call it a day  :).

I've also added an option to the phpunit plugin.  You can now add a "run_from" option and phpunit will be run from that path (relative to the root of the repo).  This was required for one of my repos that had an unusual phpunit directory structure.