netcdftime.Datetime timetuple method missing doc

[ocehugo]

Missing documentation of what timetuple returns.

In the help of e.g. DatetimeProlepticGregorian the obj hold 11 Instance/variables (year,month...), but timetuple returns only 9. I would expect that it should return all 11 variables or say at what are the returned values.

Some of them are easy to guess, but not others (last values with -1 values). Given the code is in cpython inside a .so file, not so easy to search and check.

[jhamman]

@ocehugo - we're in the process of moving netcdftime to its own, standalone package (see #601). As part of that effort, we're working on more complete documentation (see Unidata/cftime#3). It may be better to open this issue over there.