Clean up a few issues with errors

There was a output to stdout that got missed somehow, so that's
gone. Errors are handled inconsistently, so this commit starts
cleaning that up, with the goal of returning optionals rather
than using exceptions.

[#70052720]
Implement optionals instead of exceptions

[#70052720]
Merge branch 'develop' into 70052720-EpwIssues
More bug fixes to EpwFile parsing
Downgrade EpwFile error to warning

The EpwFile parser was rejecting some TMY data sets that look
like AMY datasets because the header start day of the week
wasn't matching the actual start day of the week. This commit
downgrades the error to a warning and will treat such files as
TMY-type data.

[#70052720]
Address minutes parsing in EpwFile

This commit changes how the minutes field is being handled. It is
no longer read and the number of records per hour is used to compute
the minutes value. I've never actually seen a weather file with
anything other than hourly data, do I don't have any files to test that
this works for anything but recordsPerHour=1. To make this all work
smoothly, I have removed the m_timeStep member from EpwFile and
the time step getter method now returns a value computed  from a new
m_recordsPerHour member.

[#70052720]
Add international weather file
Add additional test of international EPW file

This commit adds an additional test of an international weather
file (one of the files in issue 997). Also upgraded the original
test that checked the EPW data to do a more comprehensive check
of the dates and times in the data.

[#70052720]
Merge branch '70052720-EpwIssues' of github.com:jasondegraw/OpenStudio into jasondegraw-70052720-EpwIssues
Merge branch 'jasondegraw-70052720-EpwIssues' into develop
Merge branch 'develop' of github.com:NREL/OpenStudio into develop
Merge branch 'develop' of github.com:NREL/OpenStudio into develop
Merge branch 'develop' of github.com:NREL/OpenStudio into develop
Merge remote-tracking branch 'remotes/origin/develop' into develop
Fixes #997, file had a bunch of extra commas at the end of location line
Merge branch 'develop' of github.com:NREL/OpenStudio into develop
Updates and changes for pull request

This commit takes care of most of the issues that came up
in the pull request, including:

* Adds the additional fields to the EpwDataField enum
* Adds an additional ctor, no default arguments
* Fix return type of unitsByName
* Use openstudio::convert
* Reuses some of the setters on EpwDataField
Use EpwDataField enum in read function
Added a few more uses of EpwDataField enum
Merge branch '70052720-EpwIssues' of github.com:jasondegraw/OpenStudio into jasondegraw-70052720-EpwIssues