Cleanup
Added new GPM version command that allows to ask for the version of the Grav instance as well as any installed package. It also supports multiple arguments and if an update is available it will be shown
Cleanup
Merge branch 'develop' into feature/alternative_debugger

Conflicts:
	system/src/Grav/Common/TwigExtension.php
	system/src/Grav/Console/Cli/InstallCommand.php
	system/src/Grav/Console/Cli/SandboxCommand.php