Add front page: summary of Projects, Users, Techs, Applications

[mtso]

Feature Description

Adds several summary components to the front page for users accessing the website to see an overview and direct them to other features on the website.

High Level User Story Description
As a user
I want to see a summary of Projects, Users, Techs, Applications
So I can get an overall view of what's on the website and link to those pages

Major User Stories/tasks

• Save searches for calculating trending searches #85
• Suggested searches section #87
• Trending projects summary section
• Trending user summary section
• Trending technologies summary section
• Link to graph explorer #106

Additional Considerations
Include anything else that may be helpful. For example, links to external resources.

[mtso]

Changing this issue into an epic because there's multiple sections to the front page.

[mtso]

Un-assigning this issue from myself for now because we decided that the current front page is good enough.

I've added suggested search terms, link to the graph explorer, and the hero illustration