add linux benchmarks

README

@@ -53,6 +53,14 @@ with faster_rubygems:
   0.19s
 
 
+linux:
+
+ $ time ruby -S whichr whichr
+     ruby 1.9: 0.6s -> 0.13s
+     ruby 1.8: 0.17s -> 0.09s
+
+ Thus we see that it helps startup time for 1.9 on Linux, but not much for 1.8 on Linux.
+
 == installation ==
 
 $ gem install faster_rubygems # installs faster_rubygems into your site lib, overrides normal rubygems
@@ -107,4 +115,4 @@ http://github.com/jeremyevans/zozo
 
 Source/feedback:
 
-http://www.github.com/rdp/faster_rubygems
+http://www.github.com/rdp/faster_rubygems