SQL: many keywords and functions

extended list of keywords and functions.
MySQL 5 syntax
Alias for Objective-C

On GitHub, the `objc` alias is often used. Can we add it?
Also, is it possible to add `obj-c` (with a dash)?
Merge pull request #390 from xslim/patch-1

Alias for Objective-C
Add obj-c as alias to objectivec
Add new Obj-C aliases to CSS classes reference
Hightlight returns keyword for protobug rpc services
Merge branch 'better_protobuf_definition'
Hightlight returns keyword for protobug rpc services
New: add more functions of T-SQL
Merge remote-tracking branch 'isagalaev/master' into sql_improvements
Merge remote-tracking branch 'neor-ru/patch-4' into sql_improvements

Conflicts:
	src/languages/sql.js
Bye bye aggregate
Use beginKeywords, drop extra relevance for ilike keyword
Respect new contributors
Merge export.html into test.html
Merge pull request #394 from Sannis/merge_test_and_export_html

Merge export.html into test.html
Unique and order SQL keywords
Fix JS for markdown definition
Merge remote-tracking branch 'origin/master' into sql_improvements
Some more JS style fixes