ExtensionInstaller: Use Utils::system instead of system
Releasing 1.8.16
Bump version to 1.8.17
Releasing 1.8.17
Bump version to 1.8.18
Releasing 1.8.18
Releasing 1.8.18
Add composer.json
Add support for config0.m4 file in extension directory
Releasing 1.8.18
Checking in changes prior to tagging of version 1.8.19.
Update composer dependency
update composer dependency
update .travis script
Merge branch 'master' into 1.9

Conflicts:
	package.ini
	package.xml
	phpbrew
	src/PhpBrew/Command/InitCommand.php
	src/PhpBrew/Command/InstallCommand.php
	src/PhpBrew/Console.php
fixed update-init-script output pointless newline bug
Refactor configuration file task to class
more directory methods
Add __set_state for supporting seraizlieation
Implement the interface of Serialiabe