Update README.md

Author: lubieniebieski

README.md

@@ -16,13 +16,19 @@ If you want to include a localization file, also add the following directive:
 
     //= require locales/bootstrap-datetimepicker.<locale>
 
-Add the following line to your stylesheet file (`bootstrap_and_overrides.scss`):
+Add the following line to your stylesheet file (`bootstrap_and_overrides.scss`) :
 
 ```scss
 @import 'bootstrap';
 @import 'bootstrap-datetimepicker';
 ```
 
+or if you're having problems (or using less) require it in your main stylesheet manifest file:
+
+```scss
+*= require bootstrap-datetimepicker
+```
+
 ## Usage
 
 See the excellent demo provided by plugin's author - [@tarruda](https://github.com/tarruda) [here](http://tarruda.github.com/bootstrap-datetimepicker/).