Added detection for the Pike language:

http://pike.ida.liu.se/
Added support for the CLIPS programming language

CLIPS or C language integrated production system is a tool for writing expert
systems.
Fixed an issue where the lexer was not explicitly stated for CLIPS
Datomic dtm files
(BFDD) build-system failure driven development
better: edn is generic
Added Xtend (xtend-lang.org) to languages.yml
remove redundant specification
Detect cython-generated files
Treat .opencl files as OpenCL
Added samples for Xtend
XSLT as a programming language
Reverted pike tests until such time as we have a pike lexer here.
Correct documentation, README grammar.
Add Rouge.
Merge pull request #397 from unnali/rouge

Rouge
Merge pull request #318 from stuarthalloway/master

Datomic DTM files
Remove extra lexer
Alphabetize
Merge pull request #376 from evanmiller/detect-opencl

Treat .opencl files as OpenCL