partial upload board funtionality

[okrayum]

I was able to set up the board upload with primarily using the code Jeremy had implemented, I changed one of the components to async/await like the comments said. the issue is that the upload goes correct with board and cards, but the template preview is not getting the correct details like time and cards, and when you click the template preview no cards are shown.
Another issue that I didn't look into yet is after download an imported board it double the Create New Card button in the backlog column.

[okrayum]

Also you notice the 4 hardcoded boards briefly when clicking to search templates before seeing your uploaded boards. Which are removed if you do as Jeremy noted earlier: replace dummyTemplates with [ ]. But then no dummyTemplates at all unless do a conditional render with them in the return.

[Alforoan]

good job!