scss.lang, less.lang: Add new languages

SCSS (a newer syntax of Sass[1]) and Less[2] are two popular
preprocessor style sheet languages that are interpreted or compiled into
CSS. This adds language definitions for these two languages.

This also depends on the extensibility changes in !1.

[1] http://sass-lang.com/
[2] http://lesscss.org/

data/language-specs/Makefile.am

@@ -65,6 +65,7 @@ LANGUAGES =			\
 	julia.lang		\
 	kotlin.lang		\
 	latex.lang		\
+	less.lang		\
 	lex.lang		\
 	libtool.lang		\
 	llvm.lang		\
@@ -110,6 +111,7 @@ LANGUAGES =			\
 	scala.lang		\
 	scheme.lang		\
 	scilab.lang		\
+	scss.lang		\
 	sh.lang			\
 	sml.lang		\
 	sparql.lang		\