update spec and regen code - #237

@joelwurtz Is this project still alive? This pr fixes issue #238

Yes it is still alive, just have 0 time for the past months to deal with current problems. I try to merge directly if the PR is good enough, but this is not the case here.

There is the possibility to use a specific date time format in jane, it will be far better than using a string.

@joelwurtz ,
I cannot find any solution for the problem about nanoseconds format.
And I add the date-time format Y-m-d\TH:i:s.uuP, the double u is a tricky way to parse for nanosecond

This should be good on 2.0