Make it possible to `require "therubyracer"`.

It's common practice to be able to require the name of the gem. For
example, bundler requires the gem name by default. This removes an
element of surprise when using the gem.

README.md

@@ -24,7 +24,7 @@ then in your Ruby code
 
     require 'v8'
     # or if using bundler (as with Rails), add the following to your Gemfile
-    gem "therubyracer", :require => 'v8'
+    gem "therubyracer"
 
 evaluate some simple JavaScript
 
@@ -173,4 +173,4 @@ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 [1]: https://github.com/cowboyd/libv8
-[2]: http://code.google.com/p/v8/wiki/BuildingWithGYP
+[2]: http://code.google.com/p/v8/wiki/BuildingWithGYP

lib/therubyracer.rb

@@ -0,0 +1 @@
+require "v8"