Valididate email addresses before we throw them into the struct

It has a couple of nasty crashes at the moment..
Better checking for valid email addresses

Still has a couple of awful crashes though... At least the memory corruption
seems to be gone..
Let's add LIMIT 1 to our select queries when we simply check if it's there
Merge branch 'master' into dev
Let's just check for 'valid' characters before we do the general command check

I'm leaving in the validateEmailAddress function just because some
characters that are allowed in commands are not allowed in email addresses.
<> for example, besides the validateEmailAddress function also checks if
it has 1 @ sign..