Fixed Serialization of AbstractEntity
minor #44 [RFR] Fixed Serialization of AbstractEntity (tucksaun)

This PR was merged into the 2.x-dev branch.

Discussion
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[RFR] Fixed Serialization of AbstractEntity

Currently the serialisation of `ConnectToken` trigger the serialisation of `ApiUser`.
However the serialisation of `ApiUser` is naive and nothing in particular is done.
This leads to a really big string (~500 Kb in my case) and can lead to potential break (in my case only in production :/) because of the serialisation of `SensioLabs\Connect\Api\Api`.
Moreover there is no advantage of serialising it as it's not usable afterwards (see #15).

Commits
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9dd6e1e Fixed Serialization of AbstractEntity