If we always refresh on focus then we will
be making many redundant requests, as well as
causing the list to jump around whenever we
navigate back/forward.
The only downside to this is occasionally the
data may be stale, however the user can just
pull down on the list to refresh.
Closes#165
If `bests` is always an empty array then our logic
for detecting zero graphs is wrong. Now when we haven't
loaded any data `bests` is undefined instead of []
Every time we create/update/delete fire a DeviceEventEmitter
event for gym sets. Then we subscribe to the changes in relevant
components.
Also fixed flickering of "No data yet" on graphs page.
I was considering adding weight tracking,
so then this graph page would include body
weight graphs. Meaning it's not really
recording the "best" of anything.
It currently only shows the best on the list
page anyway.
