Fix CreateRaw() flags and timestamps

[saracen]

When the standard Go library's version of CreateRaw was added, rather than solely focus on custom compression in "raw" mode, it also removed the convenience of setting up common zip flags and timestamp logic.

This change duplicates some functions from archive/zip to add the flags and timestamp logic to CreateRaw().

This fixes an issue raised by a user of GitLab-Runner https://gitlab.com/gitlab-org/gitlab-runner/-/issues/28928 where timestamps were missing whenever CreateRaw was used.

[codecov-commenter]

Codecov Report

Merging #37 (f81e364) into main (998be6b) will decrease coverage by 0.26%.
The diff coverage is 77.50%.

@@            Coverage Diff             @@
##             main      #37      +/-   ##
==========================================
- Coverage   77.77%   77.51%   -0.27%     
==========================================
  Files          11        9       -2     
  Lines         693      716      +23     
==========================================
+ Hits          539      555      +16     
- Misses        108      114       +6     
- Partials       46       47       +1     

Impacted Files	Coverage Δ
archiver.go	78.18% <77.50%> (-0.25%)	⬇️
extractor_windows.go
archiver_windows.go

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