Remove use of Gravatar's force default parameter

Possible oversight in the inclusion of Gravatar's force default parameter? Miscellaneous comment fixes included as well.

Any thoughts on providing an option to use secure Gravatar requests or even defaulting to it?
```
http://www.gravatar.com/avatar/205e460b479e2e5b48aec07710c08d50?s=80&d=mm&r=g
```
to
```
https://secure.gravatar.com/avatar/205e460b479e2e5b48aec07710c08d50?s=80&d=mm&r=g
```