Add validation for email fields

[cekk]

Return 400 if there is an email field and the value is not a valid email string

[coveralls]

Pull Request Test Coverage Report for Build 7473952234

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 89.664%

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Totals
Change from base Build 7462752765:	0.1%
Covered Lines:	668
Relevant Lines:	745

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💛 - Coveralls

[cekk]

@JeffersonBledsoe ok seems reasonable.

I am going to close this pr and then you can sync your and fix possible conflicts, then i will merge it