Remove Dates REQUIREment

Will not make FM v0.2 backward compatible with 0.3+
Revert "Remove Dates REQUIREment"

This reverts commit 1341a4a403f2fdcf809b1edce3ddacaee17d5762.
Type field names no longer Real but Float64

Prompted by this:
https://groups.google.com/d/msg/julia-users/Kn9NO3Nu96I/OYXoR3ml73UJ

And noted that one of the default constructors converts inputs to types
specified so that if field value provided is an Int, the type
constructors converts to Float64.
Removed debug output