if configured renderer is not found, try to fallback to a bundled renderer
add test for p_get_renderer() with fallback
remove reference operator from p_get_renderer() declaration, not required for php5
add renderers to autolader
rework p_get_renderer() for use with autoloading bundled renderers
code cleaning - add some braces
change to an Exception and expect it
revert back to trigger error
remove rendundant msg
remove require handled by autoloader
Merge pull request #571 from splitbrain/renderer_graceful_fallback

Renderer graceful fallback