contrib: Explain explicit header guards #940

1. 
   real-or-random commented at 3:14 pm on May 6, 2021: contributor

   They were added in #925 and deserve a comment.
2. contrib: Explain explicit header guards

   They were added in #925 and deserve a comment.

   22a9ea154a
3. 
   gmaxwell commented at 6:29 pm on May 6, 2021: contributor

   ACK 22a9ea154a280987be7cf8322156c8738c41c3c5
4. 
   sipa commented at 3:09 am on May 12, 2021: contributor

   ACK 22a9ea154a280987be7cf8322156c8738c41c3c5
5. sipa merged this on May 12, 2021
6. sipa closed this on May 12, 2021

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7. surinder83singh referenced this in commit 3855601992 on Jun 2, 2021
8. vmta referenced this in commit 780707485f on Jun 9, 2021
9. jonasnick cross-referenced this on Jun 14, 2021 from issue Upstream PRs 831, 907, 903, 889, 918, 906, 928, 922, 933, Merge bitcoin-core/secp256k1#936: Fix gen_context/ASM build on ARM, 925, 937, 926, Merge bitcoin-core/secp256k1#940: contrib: Explain explicit header guards, 850, 930, 941, 846, 947, 662, 950 by jonasnick
10. jonasnick referenced this in commit 6db00f5b2e on Jul 13, 2021
11. sipa referenced this in commit c020cbaa5c on Jul 14, 2021
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13. apoelstra referenced this in commit 196c993d1f on Jul 28, 2021
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Contributors
real-or-random gmaxwell sipa