Download treatments originated from xDrip as well

[Navid200]

We have two open issues related to the transfer of treatments to and from followers:
#735
#1196

This PR creates a workaround:

This PR will allow a follower to download treatments uploaded to Nightscout by the master.
It also allows the master to download treatments uploaded by the follower.

1- In order for the follower to be able to upload to Nightscout, Settings −> Cloud Upload −> Nightscout Sync −> Enabled must be set.
Also, Settings −> Cloud Upload −> Nightscout Sync −> Extra Options −> Upload treatments must be enabled.

2- For the master to download treatments, Settings −> Cloud Upload −> Nightscout Sync −> Download treatments must be enabled.

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Tests

I have done a test with two test phones set up as a master and a follower confirming that treatments can be uploaded from either phone and the other phone would download it as well after this PR.

[Navid200]

This may be considered a conflict as how the follower needs to be set. It's hardware data source must be set to Nightscout follower. But, in order for it to be able to upload treatments to Nightscout, Nightscout sync also needs to be enabled.

One may wonder that the readings downloaded by the follower when then be uploaded again to Nightsocut.
My understanding is that Mongo will address such collisions.
So, there will be no issue on Nightscout.

If you ask me the following question, I cannot answer and will need to investigate if needed:
Will the follower use data to download and then again use data to upload the same data back to Nightscout? is that not a waste of data?

If this indeed is a concern, we will need to add a conditional to only upload treatments from a follower and not readings as well.

[jamorham]

I would suggest making it a preference switch for advanced option with defaulting to off so it can be merged for wider testing but I would think there could likely be a good reason for that duplicate checking being in there.

[Navid200]

That makes perfect sense. Thanks

[Navid200]

I have added a switch. The following shows before and after of the main menu:

Before	After

The following image shows the new submenu:

[Navid200]

Tapping on download treatment takes you to a new submenu. There, you have the old download treatment checkbox. But, in addition to that, you will also see a new switch called skip items from xDrip. This new switch is enabled by default, which makes xDrip behave as it did before.

If you disable this switch, xDrip will also download treatments that have been uploaded to Nightscout by another xDrip.

I hope this is acceptable.

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Tests

I have tested again two test phones acting as master and follower. Leaving the new switch enabled (default), xDrip behaves as before and does not download treatments from the other phone.
Disabling the new switch, either phone downloads treatments uploaded by the other phone.

[Navid200]

I have added the ability to set/unset the new setting in the follower menu as well.

Before	After

[Navid200]

And this is the follower submenu:

[jamorham]

looks good

[Navid200]

Thanks