Add staticSource shortcode parameter to eclipsefdn_projects shortcode

Blocks eclipsefdn/it/websites/eclipse.org-research#64 (closed)

The eclipsefdn_projects shortcode needs to have a parameter named staticSource which will act as an alternate data source to the official projects API. This staticSource should be a boolean to let eclipsefdn_projects.js in Solstice Assets know to use a different API for the given url.

A scenario which this will be used would be for the eclipse.org/research page which needs a project list based on the site's content pages (where every page is a project) instead of live data.