Use file locks in file caches

[ryanpdx]

Just before the OreSat0.5 handoff, we had an issue were the Updater service would try to move the update from the fwrite cache while the update was been upload/written. We did a last minute hack to only have the updater move file from the fwrite cache on the apps start up. If we use file lock, Updater service would wait until the file is unlocked and then move the update to its own private cache.

To solve this issue use files locks in OreSatFileCache.