Implement an easier way to install/backup Live templates

I recently used `install-live-templates` to install/backup my Live templates, and it's pretty useful!
I just implement a "registry" json file and updates documentation.

Following changes:
- Implement install-live-templates registry file to make easier the installation/backup of theses live templates,    - Update README Installation & Jasmine list part
- Create .gitignore to avoid .DS_Store and .idea files to be part of commit :)

Enjoy it!
Bon dév'