Revert constructor arguments to old order for custom installers
Use call_user_func for PHP < 5.4 compatability and accept __invoke
Load plugins from global vendor dir too
Fix file layout in unit tests

Changes made in previious commit made the output of the file change,
which in turn broke the unit tests. This commit updates the fixtures to
match the new output.
Load plugin code from global vendor dir correctly
Fix parsing of trunk in SvnDriver, fixes composer/satis#88
Merge pull request #2221 from Alan01252/fix-unexpectedas

Fix parse error thrown in PHP5.5+
Make sure directories we are downloading to are empty

We already clear them on error anyway and usually they should be
empty, but just to be safe.
Merge remote-tracking branch 'github-composer/master' into plugins

* github-composer/master:
  Make sure directories we are downloading to are empty
  Fix parsing of trunk in SvnDriver, fixes composer/satis#88
  Fix file layout in unit tests
  Fix parse error thrown in PHP5.5+
Correct FileDownloaderTest for invalid checksum
Merge remote-tracking branch 'github-composer/master' into plugins

* github-composer/master:
  Correct FileDownloaderTest for invalid checksum

Conflicts:
	tests/Composer/Test/Downloader/FileDownloaderTest.php
Load plugins and installers prior to checking installed packages
Fix undefined index error, fixes #2224
Merge pull request #2210 from Firehed/master

Change 'generated' notice to @phpdoc-style annotation
Added Perforce VCS to Composer.
Added Perforce utility class, PerforceDriver and PeforceDownloader
Added PerforceDriverTest
Updated Factory, VcsRepository to incorporate Perforce classes.
Modified ArchivableFilesFinderTest to skip Mercurial test that does not work for me.
Added Perforce to Composer
Cleaned up perforce code
Checks to see if already logged in to Perforce, and prompts for password if not and P4PASSWD is not set
Checks server url with perforce call
Checks for composer.json file, and returns the contents of the file already retrieved.
Updated Perforce driver to use labels
dev checkin, lots of cleanup to do
Cleanup phase 1
Removed branches - only returning the "master"
Finished cleanup of debug messages.