Changes

mnesia_db_euicc: renovate handling of euicc table (mnesia, REST)

The REST API that allows users to set certain eUICC parameters
(we call them "states" from now on) only allows to set eUICC
states, but doesn't allow to read them back.

With this patch, we renovate the handling of the mnesia euicc
table from the ground up so that REST API users have read and
write access to the states stored in the mnesia euicc table.

Change-Id: I74c602555b194a28d6eb9dd67ec4c6a8865fcb77
Related: SYS#8100