Reintroduce solarized-termcolors.

Fixes #94.

It now has a different purpose. In a 256-color term, setting this to 16
will try to use the exact Solarized colors, while setting it to 256 will
use the approximations.

README.md

@@ -83,6 +83,7 @@ but does include several variables that can be customized.
 
     variable name            default   optional
     --------------------------------------------
+    solarized-termcolors =   16    |   256
     solarized-degrade    =   nil   |   t
     solarized-bold       =   t     |   nil
     solarized-underline  =   t     |   nil
@@ -94,6 +95,19 @@ but does include several variables that can be customized.
 
 ### Option Details
 
+*   solarized-termcolors
+
+    Some 256-color terminals also allow you to set and use the standard 16
+    colors in addition to the fixed 256-color palette. This option only
+    applies when your terminal is in 256-color mode. If set to 16 (the
+    default) it will try to use the exact Solarized colors (assuming that
+    you've set these colors to the correct Solarized values either manually or
+    by importing one of the many colorscheme available for popular
+    terminal emulators). If it’s set to 256, then Solarized will use a
+    degraded version of the Solarized palette by displaying the closest colors
+    in the terminal's default 256 colors as shown in [Xterm's color
+    chart](http://en.wikipedia.org/wiki/File:Xterm_color_chart.png).
+
 *   solarized-degrade
 
     For test purposes only; in GUI mode, this forces Solarized to use the 256

solarized-definitions.el

@@ -5,6 +5,15 @@
   "Color theme by Ethan Schoonover, created 2011-03-24.
 Ported to Emacs by Greg Pfeil, http://ethanschoonover.com/solarized.")
 
+(defcustom solarized-termcolors 16
+  "This is set to 16 by default, meaning that Solarized will attempt to use the
+standard 16 colors of your terminal emulator. You will need to set those colors
+to the correct Solarized values either manually or by importing one of the many
+colorscheme available for popular terminal emulators and Xdefaults."
+  :type 'integer
+  :options '(16 256)
+  :group 'solarized)
+
 (defcustom solarized-degrade nil
   "For test purposes only; when in GUI mode, forces Solarized to use the 256
 degraded color mode to test the approximate color values for accuracy."
@@ -124,7 +133,8 @@ the \"Gen RGB\" column in solarized-definitions.el to improve them further."
                                              (solarized-broken-srgb 2)
                                              (t                     1))))
            (((background dark) (type tty) (min-colors 256))
-            ,(solarized-face-for-index facespec 3))
+            ,(solarized-face-for-index facespec
+                                       (if (= solarized-termcolors 16) 4 3)))
            (((background dark) (type tty) (min-colors  16))
             ,(solarized-face-for-index facespec 4))
            (((background dark) (type tty) (min-colors   8))
@@ -136,7 +146,9 @@ the \"Gen RGB\" column in solarized-definitions.el to improve them further."
                                              (t                     1))
                                        t))
            (((background light) (type tty) (min-colors 256))
-            ,(solarized-face-for-index facespec 3 t))
+            ,(solarized-face-for-index facespec
+                                       (if (= solarized-termcolors 16) 4 3)
+                                       t))
            (((background light) (type tty) (min-colors  16))
             ,(solarized-face-for-index facespec 4 t))
            (((background light) (type tty) (min-colors   8))