Update lib/linguist/languages.yml

Add DOT language: http://www.graphviz.org/content/dot-language
Update lib/linguist/languages.yml

Add .gv (GraphViz) file extension to DOT language.
New language: XProc - an XML Pipeline language (W3C)
added XML lexer
More Forth samples.
Added matlab code samples.
All of these code samples currently are mis-identified in my repositories. I'm
donating them to the cause.
Update lib/linguist/languages.yml

Change sort order
Update lib/linguist/languages.yml

Set lexer to Text only for DOT. This hopefully fixed the failure on Travis.
Added one more file
Minor README fixes
Fixed typos
Merge pull request #419 from pborreli/typos

Fixed typos
Remove extra Forth extension
Update samples.json, bump to 2.6.3
Remove out of date notes
Add ABAP
Add support for the Logos language.
Update samples.json to include Logos.
Turn on Rust lexing. Add a bigger sample
Merge pull request #294 from DHowett/master

Add support for the Logos language.