Currently, build logs are not loaded when the tab is in the background. However, when switching back to the tab, there is no indication that logs have not loaded, and it can take up to the poll duration (5s) before we even start loading the logs. This change adds a message displayed for the user before the logs start to load to indicate they are being refreshed and also *immediately* starts the loading of the logs when the tab is made visible.
Fixes#501