Progress Bar for Scanning the Blockchain

[chriseling]

It would be great if there was a progress indication when scanning the blockchain. I'm new to SIA and the new user experience is important for adoption. I'm not sure how long the scanning will take and then the program on Mac hide and I unlocked my wallet and it started scanning the blockchain again. I get why it's important to scan, but for a new wallet and new users, progress indication would be a nice feature.