Add a default initializer

[leandroluk]

First of all sorry for my English, I had help from google translate =D

Hello, I'm starting to use your project and I saw that there is no automatic startup tag when rendering. It would be interesting to create an autostart method just as it exists in other libraries that work with the bootstrap (the bootstrap itself already does) by setting a tag on the element that will be initialized automatically, something like:

<input type="checkbox" boostrap-switch /> <!-- auto initialized! -->