Sender uploadspeed and Receiver progress

[eric-m-truong]

Uploading and Downloading now display the upload speed and download progress, respectively. This makes the UI look a bit more responsive and lets the user know that the page isn't frozen.

Testing

1. Open 2 instances of the front-end
2. When choosing files to upload, pick a large file if you can.
3. Larger files take longer to download/upload
4. Larger files may also take longer to generate magnet links for, so be patient
5. Initiate the Bump as usual
6. Observe that the Receiver has a Progress percentage.
7. Observe that the Sender has an Upload Speed in bytes/second

[samilkk]

It works great! I tested with big and small files on both desktop and mobile. Additionally, I tried with turning off the wifi in the middle of the transfer, and the progress bar continued from where it was left. Great job!