Module Overhall / Improvements

I submitted an issue to the queue just the other day and after spending more time reviewing, decided it was probably best to just make a few major changes and submit a patch with them all together. I'm open to feedback on the changes I've implemented.

Permissions
The module previously did not invoke hook_permissions and set the 'administer facebook comments box' permission value to be set when configuring permissions. This is not an issue if you are always logged in as UID 1, however, all other users will not be able to inherit this permission without it. I've added this to the new version.

Theme Layer
When the block is being built, the meta markup and html markup are being built directly in the callback function. This prevents other developers from making custom modifications to the markup by use of template overrides and just bad practice all together. I've pulled out both the meta and html markup and implemented their own themes / templates for each. This will insure future developers have the ability to override as needed without hacking the module.

Administration / Configure Settings
One thing I didn't understand was why there is a setting to choose which node types the comments should be visible on. Since the module was designed to be block driven, this logic kind of clashes with itself since in you have the ability to define where a block shows up in the block admin configuration or by using a contrib module like contenxt. Since this is block driven, the module should allow for the block to set the visibility vs the module itself. You'll run into a lot of confusion when the block visibility is set to display on content type x but the module says not to display the comments on that content type. I've removed this configuration from the new version of this module. The only way the module should provide this setting if the comments are being attached to the node via the module, not block driven.

Summary
I made a lot of changes here so I understand if there is hesitation to move forward. My goal is provide a more stable module from the current version and to address some relatively important concerns that may have gone overlooked.