Allow users to review and vote on various aspects of projects.

In #2186377: Highlight projects that follow Best Practices we aim to introduce an automatically calculated indicator based on various measurable factors from data gathered. This issue here is to request to allow users to vote on various project aspects that we cannot literally measure per se like:

- accuracy of the project's description
- completeness of documentation (both in the module's README.txt/INSTALL.txt as well as its documentation pages in d.o)
- fast replies in the queue (not necessarily by the maintainers)
- an overall "feeling" based on how useful the module is and whether it has any similar

Here are some examples of how it's done elsewhere...

Rating of addons in mozilla.org. There's an average next to the addon's name:

...+ a detailed breakdown further down the sidebar:

Rating and reviews of apps in Google web store:

Rating of user profiles on ebay as well as rating of sellers based on various factors: