Updated simplepie (bugfix) and README

Dear Chris,

Latest 0.0.5 is fixing all my CSS issues.

Due to my poor javascript knowledge I cannot contribute much to leDashboard, but:

 - I have updated the README so as it renders nicely in github (markdown is nice and easy to read in my opinion).

 - Some widgets were not being loaded propely, leaving an error in the PHP log. I found that by updating simplepie to the latest bugfix release, all widgets were working properly. The fixed bug in simplepie is found at: https://github.com/simplepie/simplepie/issues/214 

I hope this time I am helping you a bit instead of messing things up ;-)

Best regards,

Sergio