Added two new options 'toread' and 'shared' and updated Readme.org to reflect changes

Added two new options: -toread and -shared. closes #5 and #6.
Updated Readme.org to reflect the new options.

Please review keeping in mind that this is my first ever use of github and of git. I'm not a professional programmer and have no javascript experience, but tried to follow your logic and made the changes. I've tested the new options briefly and the new options work as expected. I'm now using the modified version on my box. 

I made the changes locally, and I wanted to 'give back' and share my changes with you. Whether or not my changes meet your standards, please accept my gratitude for creating this plugin and sharing it.