Reduce the number number of S3 PutRequests and size of uploads

[dakotabenjamin]

MapCampaigner doesn't scale too well with numerous large campaigns. It makes a ton of regular PutRequest s3 API calls which can add up over time.

Some initial thoughts to improving this problem:

• smart updating based on user interaction
• regularly update partial data with manual option for full updates
• limit AOIs, campaign lengths, zoom levels, etc.
• rather than delete all date and reupload, intelligently update (sync?)