[v0.14.x] Configurable CoreDNS TTL

[dominicgunn]

Changes

• Allows a configurable TTL for CoreDNS.

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[codecov-io]

Codecov Report

Merging #1626 into v0.14.x will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff             @@
##           v0.14.x    #1626      +/-   ##
===========================================
- Coverage    25.54%   25.54%   -0.01%     
===========================================
  Files           98       98              
  Lines         5038     5039       +1     
===========================================
  Hits          1287     1287              
- Misses        3608     3609       +1     
  Partials       143      143

Impacted Files	Coverage Δ
pkg/api/types.go	0% <ø> (ø)	⬆️
pkg/api/cluster.go	0% <0%> (ø)	⬆️

---

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[codecov-io]

Codecov Report

Merging #1626 into v0.14.x will decrease coverage by <.01%.
The diff coverage is 0%.

@@             Coverage Diff             @@
##           v0.14.x    #1626      +/-   ##
===========================================
- Coverage    25.54%   25.54%   -0.01%     
===========================================
  Files           98       98              
  Lines         5038     5039       +1     
===========================================
  Hits          1287     1287              
- Misses        3608     3609       +1     
  Partials       143      143

Impacted Files	Coverage Δ
pkg/api/types.go	0% <ø> (ø)	⬆️
pkg/api/cluster.go	0% <0%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 63ffc1f...a32671a. Read the comment docs.

[davidmccormick]

Would you be so kind as to also PR this to master? Then I will merge both 🙏

[dominicgunn]

Here you go @davidmccormick, #1627.