Redesign: replacing current project tiles with new ones from figma mockup

Currently project tiles require you click in to a modal, we've redesigned them with a call to action button and added a active tag.

Old:

New:

## Details:

* We will need a short description for each project. Let's be sure to check the description with the project.
* This might be a good time to check in to see which projects should be featured on the tiles.
* We might also want consider how many tiles we'd like on the page. Let's start with eight or less and go from there.
* "Read More" buttons should lead to project page.
* For example: the "read more" button for Choose Native Plants PA would lead you to https://codeforphilly.org/projects/pa_wildflower_selector
* Lets add direct links for github, and project website on each tile, similar to Hack for LA, and test it out on some users?

Comece localizando o ponto de entrada existente de project-tile e comparando-o com o mockup do Figma. Confirme as descrições dos projetos, a lista de projetos em destaque, a quantidade de tiles, os destinos de Read More e os links diretos para o GitHub e o site do projeto antes de implementar e testar os tiles redesenhados.

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