Fix copy/paste bugs

[laborg]

The refactored method is quite buggy. I assume that its not used that often, otherwise those bugs would have surfaced by now. Nevertheless this should be an improvment in terms of performance and correctness.

Improved performance

const ts = [DateTime("2017", "yyyy"), DateTime("2018", "yyyy"), DateTime("2019", "yyyy")]
@btime oldshowoff($ts)
@btime showoff($ts)

 7.991 μs (112 allocations: 5.38 KiB) # master
 5.386 μs (64 allocations: 2.59 KiB) # pr

Changed (IMHO corrected/intended) behaviour:

Milliseconds are now shown, if they are provided

x = DateTime.(["2017-04-01T12:00:00","2017-04-01T12:00:00.001","2017-04-01T12:00:00.123"]);

"Apr 1, 2017 12:00 |  12:00 |  12:00" # master
"Apr 1, 2017 12:00:00.000 | 12:00:00.001 | 12:00:00.123" # pr

Milliseconds are now hidden, if there aren't any

x = DateTime.(["2017-04-01T12:00:00","2017-04-01T12:00:01","2017-04-01T12:01:00"]);

"Apr 1, 2017 12:00:00.000 |  12:00:01.000 |  12:01:00.000" # master
"Apr 1, 2017 12:00:00 | 12:00:01 | 12:01:00" # pr

Seconds are now hidden, if there aren't any

x = DateTime.(["2017-04-01T00:00:00","2017-04-01T01:00:00","2017-04-01T12:34:00"]);

"Apr 1, 2017 00:00:00.000 |  01:00:00.000 |  12:34:00.000" # master
"Apr 1, 2017 00:00 | 01:00 | 12:34" # pr

Day is hidden, if all days are the first day of month

x = DateTime.(["2017-04-01T00:00:00","2017-05-01T00:00:00","2017-06-01T00:00:00"]);

"Apr 1, 2017 | May | Jun" # master
"Apr 2017 | May | Jun" # pr

[codecov]

Codecov Report

❌ Patch coverage is 31.81818% with 30 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.79%. Comparing base (e510033) to head (483d8ed).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/Showoff.jl	31.81%	30 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #48      +/-   ##
==========================================
- Coverage   84.65%   80.79%   -3.87%     
==========================================
  Files           2        2              
  Lines         189      177      -12     
==========================================
- Hits          160      143      -17     
- Misses         29       34       +5     

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