Fix issue where none root composer.json could be used by ArtifactRepository http://www.php.net/manual/en/ziparchive.locatename.php#85512
Improved variable name.
Package should have download options
Package options must be passed as argument to downloader
Package options should be dumped if exists
Package options must be a non mandatory array and should be loaded when
exists
Repository options must be replicated on package when dist file is under
repository base dir
Improved the handling of trunkPath

- $this->baseUrl is only used if $this->trunkPath === false, otherwise
we will use $this->baseUrl with $this->trunkPath.
- scanning through trunkPath will now look for composer.json file
instead of a path that matches $this->trunkPath, beacuse checking
against the latter failed with deeper trunkPaths
- $this->rootIdentifier is now 'trunk' no matter how deep
$this->trunkPath is (with deeper trunkPaths, the name became something
like "dev-trunk-devel-team-packages-package"
Fixed a coding style issue

Missing a space between if and (
Add a warning for unbound constraints in the validating loader

Closes #2165
Added a new FAQ entry about unbound version constraints
Fail hard if anything attempts to wipe the entire filesystem/partition, fixes #2409
No need to create hg working copies just to parse tags/branches
Merge pull request #2427 from webfactory/hg-no-working-copy

No need to create hg working copies just to parse tags/branches
Use cache directory when downloading composer.phar

Since there is a cache dir there is no need to populate the project
directory with temp files. Plus the permissions on the project dir
might not allow that.
Check if current dir is writable and if not try the cache dir from settings
Cache path never ends with '/'
Merge remote-tracking branch 'jimmykane/master'
Add preFileDownload event on package.json fetch
don't require the error message have the first line of HTTP output in it