Devices and group config prevalence and priority

[mapedraza]

The problem

When data from a non provisioned device (I.E: DEV001) arrives to the IoTA through a certain group and APIKEY, automatically a devices is created with an specific entity_id associated based on entity_type and device_id

If the group is edited by adding a new parameter, entityNameExp then, new entities will be created, according to the new group expression, but device will contain the old entityID, wich leads to confussion.

The actual behavior is the desired, but, in case a device need to be remaped, it should not work (being used the entityNameExp instead the forced value)

This can be solved by removing the entityId value when creating the device. This should mean the group parameter, no matter if the entityNameExp is defined, or the default patter (<entityType>:<deviceId>) is going to be used. If entityId is defined in the device configuration, it should be used instead of the expression.

Be aware that, if the preference is solved, but the IoTA still keep copiying the entityId into the device, it could be incompatible with running deployments.

To be discussed in call
CC: @danielvillalbamota

[mapedraza]

Document behaviour into the doc

[mapedraza]

After merging #1663 this issue can be closed