Merge pull request #44 from domu1de/dev

Prevent circular dependencies
Fixed exception thrown by Container::get
#46 PSR2 guide style
#46 PSR2 guide style in the documentation
Preventive fix regarding https://bugs.php.net/bug.php?id=61384 (thanks Scrutinizer-CI)
Change log
#39 Fixed documentation links
Preventive fix regarding https://bugs.php.net/bug.php?id=61384 (thanks Scrutinizer-CI)
Preventive fix (thanks Scrutinizer-CI)
Fixed scopes documentation as the default scope is 'singleton'.