ElementRendererAbstract cleanup and build process refactoring

^ fix ElementRendererAbstract::getInstance() tests
^ refactor abstract ElementRendererAbstract::build() to simpl implementation
^ refactor build() return value from $this to string as default use case.
Content navigation link targets

^ replace #content in article nav with #the-article
- link target in pagination.php
fix showReadMore to use $target parameter
Fix category title rendering ('show_category_title'), code comments
Padawan: move js file(s) to subfolder
Fix ElementFeature::getInstace()
Changed scope of static $elements from protected to private
ElementFeatureMsie refactor

^ now extends ElementRendererAbstract (instead of Meta)
^ call Renderer instance to add meta and script data
Added ConstructTemplateHelper::getConfig() magic config $key 'template'

shortcut to read template params via getConfig()
ConstructTemplateThemeinitial support for individual feature classes.

+ renderFeature() to build()
+ missing $head['links'] to build()
^ renderFeature() to store + return the rendered string instead feature instance
ElementFeature twisted script and scripts render calls
ElementFeatureStandards twisted script and scripts renderer calls
Initial support for dedicated elements/renderer/*

^ code and comment cleanup
+ impl. dedicated function build() for various renderers
- removed redundant standard calls of build() where (yet) no magic needs to happen
^ refactored function build() to return rendered string instead of instance
Padawan: fix blog column img width, + RSS limk icon.
Add "IEMobile 7" to helper
Padawan: update Modernizr 2.6.2, weblink category styles
HTML: Weblink category item override
CSS: support for placeholder pseudo-elements
weblinks items: fixed introtext, removed noscript
editor.css colored "info" blocks

No color styles in editor available for paragraphs with .error, .warning, .notice, .message, .tips