Fixed logical operator's allowed children

Logical Operator did not check if more than 2 blocks where added when
set to == which resulted in source code error's. Now it only allows 2
when set to ==.
Removed "==" from logical operations, added notification when changing to "!"

"==" was removed from the logical operations block because it will be
part of the comparison block (not yet created)

When switching to the "!" operation the user is now prompted that it
will delete all but the first child block and asks if they would like
to continue.