Merge pull request #4 from lperichon/master

Added missing EmailFormatValidator
v0.0.7
[#42506283] removed EstimatedAge as a ContactAttribute
[#42506283] added validation to estimated age
Merge pull request #5 from afalkear/master

Removed EstimatedAge from ContactAttributes and set it as a direct attribute
v0.0.8
[#42506283] estimated age can be blank
Merge pull request #6 from afalkear/master

EstimatedAge can be blank
v0.0.9
[#23177667] Social Network Id contact attribute type