Provide additional solr facets for advanced project browsing

Since this is in the drupalorg namespace, I'm switching this to the that project, and tagging it. I'll try to review this and see if there are any duplications with the current code in drupalorg.module and if there is anything that needs cleaned up before committing.

I suppose it'd also be worth reviewing to see if there is duplicate code with project_solr, or if anything here should live in project_solr itself as well.

Okay, this module contains a version of the main D&E page that is found at /download. This partially duplicates what is in drupalorg.module HEAD right now, and also is perhaps part of the code that will be needed at: #666120: Provide API to get the top N projects for various categories(which I'll be linking to here).

I spoke briefly with Damien that other day, and he mentioned that he saw this issue and that this code is somewhat out of date and that somewhere there is a newer version that he worked on.

Most of this module should die, or is duplicate with #868794: Add an apachesolr_result_block module to render solr facet results as blocks. However, if there's anything of value in here that's not related to the theme template for the /download page itself (which really is d.o-specific) it should become a patch for project_solr, not its own module in drupalorg.

If it turns out we already have all the facets we need, just set this to "by design". ;)

Thanks!
-Derek

'Most Installed' should be 'Most installed' to be consistent with the project browsing form, no? other than that this looks pretty straighforward. has it been tested?

I'm not super familiar with the workings of this hook, but it seems like this should be wrapped within one of these:

    if (module_exists('project_usage')) {

#11 looks good. committed to 6.x-1.x-dev

per csevb10, this issue is complete.