Fixed some code blocks issues in kv and date filters docs
Merge pull request #300 from jamtur01/codeblocksfix

Fixed some code blocks issues in kv and date filters docs
Fix class discovery for Threadables
- try to clarify 'one of these things'
- deprecate the config /..../ regexp crap from date
Deprecate the regexp config crap
Deprecate regexp match shorthand for grok
Try to improve the docs for xml
Add more examples and doc improvements
- make common settings like filter 'remove_tag' use the literal plugin
  name instead of the text "myfilter" in examples.
fix one more instance of 'myfilter' -> %PLUGIN%
- link to joda's docs
- only do string conversion on symbols (config :some_symbol).
  This keeps support for regexp configs until I finally remove that.
- link to releases hosted on dreamobjects
- clean up intro on simple getting started
- fix url to point at dreamobjects
- remove dreamforce references
Point link at my puppetconf talk
- fix old changelog entry
- add metrics docs