Card component

[phated]

What's this PR do?

Adds a custom Card component instead of using the one provided by react-material, which had some styling that caused scrollbars to not be clickable. This custom one has only the bare minimum styling. The shadow on the edge of the custom card may be less pronounced because the react-material library was using a bunch of elements to generate its shadow.

What are the important parts of the code?

src/components/card.js has the definition of the custom Card component, it is then swapped out in
src/components/overlay.js and src/components/sidebar.js. Changes were also made to src/components/projects-button.js because we no longer have postition: relative on the card component to contain it (again, because we only want the minimum styles).

How should this be tested by the reviewer?

1. Create files in the sidebar until they exceed the boundaries. Verify that you can grab and drag the scrollbar (this is a bit difficult on OSX).
2. Create projects (in the project view) until they exceed the boundaries. Verify that you can grab and drag the scrollbar (this is a bit difficult on OSX).
3. Verify the visual look of the sidebar and modals look similar to the old implementation.
4. Verify all modals still behave properly.

Is any other information necessary to understand this?

Everything should be outlined above.

What are the relevant tickets? (Please add closes, refs, etc)

Fixes #277
Fixes #290

Screenshots (if appropriate)

Very hard to capture this on OSX 😞

[phated]

@PropGit can you please test this branch on Windows? I believe the issue is fixed because I can now grab the scrollbar on OSX but I want to cover all the bases.

[phated]

This change introduced a visual bug with the download progress bar. I have pushed a new commit that fixes it.

[PropGit]

@phated - Yes, I will test it in Windows and report tonight.

[PropGit]

@phated - I tested it and, yes, it is fixed now in Windows too.