Add pygments style env var for colorized

plugins/colorize/colorize.plugin.zsh

@@ -8,22 +8,30 @@ colorize_via_pygmentize() {
         return 1
     fi
 
+    # If the environment varianle ZSH_COLORIZE_STYLE
+    # is set, use that theme instead. Otherwise,
+    # use the default.
+    if [ -z $ZSH_COLORIZE_STYLE ]; then
+        ZSH_COLORIZE_STYLE="default"
+    fi
+
     # pygmentize stdin if no arguments passed
     if [ $# -eq 0 ]; then
-        pygmentize -g
+        pygmentize -O style="$ZSH_COLORIZE_STYLE" -g
         return $?
     fi
 
     # guess lexer from file extension, or
     # guess it from file contents if unsuccessful
+
     local FNAME lexer
     for FNAME in "$@"
     do
         lexer=$(pygmentize -N "$FNAME")
         if [[ $lexer != text ]]; then
-            pygmentize -l "$lexer" "$FNAME"
+            pygmentize -O style="$ZSH_COLORIZE_STYLE" -l "$lexer" "$FNAME"
         else
-            pygmentize -g "$FNAME"
+            pygmentize -O style="$ZSH_COLORIZE_STYLE" -g "$FNAME"
         fi
     done
 }