loop handling [0.8.1]

This version introduces multiple enhancements:

added handling of loops
fixed clean markers for optional data
PSR refactor changes

Details of additions/deletions below:
--------------------------------------------------------------

Modified:   Lib/Core/Render/etc/config.ini
            -- Modified --
                changed version from 0.7.1 to 0.8.1

Modified:   Lib/Core/Render/View/ViewAbstract.php
            -- Added --
                LOOP_KEY_PREFIX
                $_loopMarkerPrefix
                loop
                _renderLoops
                _renderLoop
                _getGroupMarkerContent
                _getGroupMarker
                _prepareLoopMarkerPrefix
            -- Updated --
                $_contentMarkers added new markers
                __construct added usage of _prepareLoopMarkerPrefix
                render osage of _renderLoops
                _renderLoops skip loop markers
                _cleanMarkers fixed removing optional markers