UX Improvements for explorer from IWB hackathon

Got some really excellent UX feedback during the internetborders hackathon and I will share in here some highlights:

• Add to each row in OONI Explorer for a chart (ex. the MAT chart) some sort of high level summary information. This would provide summary level information about what we know for the specified time range for the selected target (ex. Confirmed blocked or 40% anomalous measurements)
• Change the color of the coverage calendar chart to something else, we could do it ooni blue. Otherwise it's misleading that it looks like the blocked/anomaly indicators, but instead it's talking just about volume of coverage.
• Add 3 blocks in the hero unit talking about what are the main insights you can gain from OONI data: Websites, IM apps, Circumvention tools
• Inconsistent fonts and sizes in the from and until selectors on the MAT vs the domain input item
• MAT filter by default closed and with some preselected useful chart. This would improve the experience of the landing page.
• In the MAT the example placeholder should say "For example twitter.com" and the text color should be lighter
• Add search results in home page and link it to the search page

We should eventually split these up into separate issues for tracking them separately.