added a check if resource is cacheable
don't cache uncached tags, parse them always as last
added field "instantapi" that shows if output was cached before or not
added field "rendertime" that uses $modx->startTime to calculate script runtime
code cleanup
integrated parser_max_iterations system setting
added "$modx->resource =& $page;" if using a cached version
Merge pull request #4 from christianseel/master

Improved parsing of uncached tags and added resource reference for cached output