fix Twitter link in README
Twitter broke their JS-style links.
@@ -67,7 +67,7 @@ See [{file:CHANGELOG.md}](CHANGELOG.md)
- *RubyGems* *repo*: https://rubygems.org/gems/oj
-Follow [@peterohler on Twitter](http://twitter.com/#!/peterohler) for announcements and news about the Oj gem.
+Follow [@peterohler on Twitter](http://twitter.com/peterohler) for announcements and news about the Oj gem.
#### Performance Comparisons
