Package Control Compatibility Update

I've been using Phalcon for a few months and I realized the Volt syntax highlighting isn't on the [Sublime Package Control](https://sublime.wbond.net). So I decided to help you guys out with that.

I have updated the repository structure to be compatible with the [guidelines](https://sublime.wbond.net/docs/developers#Creating_a_Package_File) for submitting it with the package control. I updated the README.md with more modern language, to include ST3 and Package Control support. I also removed the theme's .cache file and added it to a .gitignore file for the project.

Once this is merged I will submit a pull request to update the Package Control's Package Listing.

Thanks for your work on Phalcon, I hope this is helpful to some folks out there.