[tz] please do not enforce limits in code for time zones

[Michael Douglass]

On 1/22/18 14:44, Lester Caine wrote:
> On 22/01/18 19:22, Howard Hinnant wrote:
>> There’s a proposal before the C++ standardization committee:
>>      https://wg21.link/p0355
>> <Disclaimer> I’m the author. </Disclaimer>
>
> Still no means of identifying if a change of version of TZ data 
> results in a change to a local time? At the end of the day which ever 
> software is being used, if I provide a UTC normalised time then it 
> also needs to identify the rule set used to create it. If different 
> software uses different ways of storing the rules it is somewhat 
> irrelevant as long as they all produce the same local time so any 
> improvements to the rules should include version information. 
> Something that has been missing for too long now.
We can make a start by adding VERSION as a valid property to the 
iCalendar format and populating it from the data.

However, I'd like to see a more fine-grained value than the current 
release. We probably also need a SOURCE property also