Fixed posix default foregroud color to use 39/default instead of...

Fixed posix default foregroud color to use 39/default instead of 37/light-gray, since was very hard to see on some dark background terminals.
Added Gemfile.lock for rubygems bundle environment consistency.

Gemfile.lock

+GEM
+  remote: http://rubygems.org/
+  specs:
+    rake (10.3.2)
+    test-unit (2.4.3)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  rake
+  test-unit (= 2.4.3)

auto/colour_prompt.rb

@@ -61,6 +61,26 @@ class ColourCommandLine
   end
 
 	def posix_colour(colour)
+    # ANSI Escape Codes - Foreground colors
+    # | Code | Color                     |
+    # | 39   | Default foreground color  |
+    # | 30   | Black                     |
+    # | 31   | Red                       |
+    # | 32   | Green                     |
+    # | 33   | Yellow                    |
+    # | 34   | Blue                      |
+    # | 35   | Magenta                   |
+    # | 36   | Cyan                      |
+    # | 37   | Light gray                |
+    # | 90   | Dark gray                 |
+    # | 91   | Light red                 |
+    # | 92   | Light green               |
+    # | 93   | Light yellow              |
+    # | 94   | Light blue                |
+    # | 95   | Light magenta             |
+    # | 96   | Light cyan                |
+    # | 97   | White                     |
+
 	  case colour
       when :black then 30
       when :red, :failure then 31
@@ -69,9 +89,10 @@ class ColourCommandLine
       when :blue, :narrative then 34
       when :purple, :magenta then 35
       when :cyan, :output then 36
-      when :white, :default_white, :default then 37
+      when :white, :default_white then 37
+      when :default then 39
       else
-        30
+        39
     end
   end