Fix tag input field

fixes #1532
- giving higher priority to css selector for .tag-input in order to override global input-style
- remove padding set by global input-style to align nicely with already set tags

![screen shot 2013-11-23 at 19 54 10](https://f.cloud.github.com/assets/7757/1607140/b82213b8-5470-11e3-93ce-040db9fe2e16.png)