Updated builtins reference

Author: Michel Casabianca

doc/builtins.md

@@ -1,6 +1,6 @@
 # Builtins Reference
 
-[absolute](#absolute) - [appendpath](#appendpath) - [changelog](#changelog) - [contains](#contains) - [directory](#directory) - [env](#env) - [escapeurl](#escapeurl) - [exists](#exists) - [expand](#expand) - [filename](#filename) - [filter](#filter) - [find](#find) - [findinpath](#findinpath) - [followlink](#followlink) - [greater](#greater) - [greaterorequal](#greaterorequal) - [haskey](#haskey) - [join](#join) - [joinpath](#joinpath) - [jsondecode](#jsondecode) - [jsonencode](#jsonencode) - [keys](#keys) - [length](#length) - [list](#list) - [lower](#lower) - [lowercase](#lowercase) - [lowerorequal](#lowerorequal) - [match](#match) - [md5](#md5) - [newer](#newer) - [now](#now) - [ospath](#ospath) - [read](#read) - [replace](#replace) - [run](#run) - [setenv](#setenv) - [sortversions](#sortversions) - [split](#split) - [termwidth](#termwidth) - [throw](#throw) - [title](#title) - [toint](#toint) - [trim](#trim) - [unescapeurl](#unescapeurl) - [unixpath](#unixpath) - [uppercase](#uppercase) - [uuid](#uuid) - [windowspath](#windowspath) - [winexe](#winexe) - [yamldecode](#yamldecode) - [yamlencode](#yamlencode)
+[absolute](#absolute) - [appendpath](#appendpath) - [changelog](#changelog) - [color](#color) - [contains](#contains) - [directory](#directory) - [env](#env) - [escapeurl](#escapeurl) - [exists](#exists) - [expand](#expand) - [filename](#filename) - [filter](#filter) - [find](#find) - [findinpath](#findinpath) - [followlink](#followlink) - [greater](#greater) - [greaterorequal](#greaterorequal) - [haskey](#haskey) - [join](#join) - [joinpath](#joinpath) - [jsondecode](#jsondecode) - [jsonencode](#jsonencode) - [keys](#keys) - [length](#length) - [list](#list) - [lower](#lower) - [lowercase](#lowercase) - [lowerorequal](#lowerorequal) - [match](#match) - [md5](#md5) - [newer](#newer) - [now](#now) - [ospath](#ospath) - [read](#read) - [replace](#replace) - [run](#run) - [setenv](#setenv) - [sortversions](#sortversions) - [split](#split) - [termwidth](#termwidth) - [throw](#throw) - [title](#title) - [toint](#toint) - [trim](#trim) - [unescapeurl](#unescapeurl) - [unixpath](#unixpath) - [uppercase](#uppercase) - [uuid](#uuid) - [windowspath](#windowspath) - [winexe](#winexe) - [yamldecode](#yamldecode) - [yamlencode](#yamlencode)
 
 ## absolute
 
@@ -59,6 +59,32 @@ Examples:
     # get version of last release:
     - 'VERSION = changelog("")[0].Version'
 
+## color
+
+Colorize string.
+
+Arguments:
+
+- The name of the color (black, red, green, yellow, blue, magenta, cyan or white).
+- The string to colorize.
+
+Color capitalization determines the intensity of the color:
+
+- Use standard color names (such as black) for normal colors.
+- Use capitalized color names (such as Black) for bold colors.
+- Use uppercase color names (such as BLACK) for bold background colors.
+- Use uncapitalized uppercase color names (such as bLACK) for background colors.
+
+Returns:
+
+- The colorized string.
+
+Examples:
+
+    # green message
+    color("green", "OK")
+    # returns: string "OK" colorized in green
+
 ## contains
 
 Contains strings.
@@ -221,7 +247,7 @@ Arguments:
 
 Returns:
 
-- Files as a list of strings.
+- Files as a sorted list of strings.
 
 Examples: