logstash service improvements

* add logstash-contrib plugins package
* add additional options to the logstash service
fritzing: add version 0.9.0b

- An open source prototyping tool for Arduino-based projects
megaglest: new package
screen: enable 256 colors
lua-packages.nix: whitespace fixes
Merge pull request #4502 from grwlf/screen-256color

screen: enable 256 colors
haskellPackages.cmdtheline: apply System.{Cmd -> Process} patch
Merge pull request #4501 from edwtjo/cmdtheline-patch

haskellPackages.cmdtheline: apply System.{Cmd -> Process} patch
Merge pull request #4475 from matejc/megaglest

megaglest: new package
Merge pull request #4456 from robberer/pkgs/fritzing

fritzing: add version 0.9.0b
Merge pull request #4392 from cstrahan/logstash

logstash service improvements