Add Http_Handler

- introduce Http module
- add Handler class
Move CM_Request_* into CM_Http_Request_*
Move CM_Response_* into CM_Http_Response_*
enable -webkit-font-smoothing for textareas as well
add textarea to example form, add placeholder
Make placeholder text more visible
adjust default font color / placeholder color
reduce emoticon size
replace generateConfigActionVerbs and generateConfigClassTypes with get-functions that return CM_Config_Node objects
evaluate class constants in array keys in CM_Config_Node::export()
implemented CM_Config_Node::exportAsString()
implemented CM_Config_Node::extendWithConfig() to recursively merge different configs
implicitly generate class types in CM_Config_Generator::getConfigClassTypes()
use new internal config generator mechanism in CM_App_Cli
generate internal config in-memory when running tests
merge arrays as well to match existing extend-mechanisms' functionality
use + operator instead of array_merge to merge numerical arrays in the same fashion as associative arrays
- docu
- use return value instead of referenced param in _evaluateConstantsInKeys
- use constant() instead of eval() to evaluate class constants
- suppress invalid constants warnings
use strict comparison when evaluating class constants to include 0-values