Merge pull request react-bootstrap#508 from AlexKVal/typo

[fixed] typo

Author: mtscout6

docs/examples/Input.js

@@ -27,7 +27,7 @@ const ExampleInput = React.createClass({
         value={this.state.value}
         placeholder='Enter text'
         label='Working example with validation'
-        help='Validates based on string length.'
+        help='Validation is based on string length.'
         bsStyle={this.validationState()}
         hasFeedback
         ref='input'