Added provider documentation page

This pull request adds links to provider specific documentation, examples, and support options as discussed in this thread:

https://groups.google.com/forum/?fromgroups=#!topic/ruby-fog/r49Bpinncrk

The new page currently lists links to all of the documentation and examples I was able to find in the Fog repo. I marked the support type as community for all providers as I was unaware of the various provider's level of commitment to fog. I am hoping to get everyone's help in filling in the missing blanks.

I would also like to this information in the fog repo as well. What are everyone's thoughts on having a link to the provider documentation on fog.io verses duplicating it in the fog repo?

Additionally, I have updated the css specific to table rendering. This should make the new provider documentation page as well as the Supported Services page easier to read.