Merge pull request chapel-lang#15513 from soohoonchoi/RAD-1354

Update Dockerfile and README for Chapel Release 1.22.0: Release Branch Only

Merge pull request chapel-lang#15471 from soohoonchoi/RAD-1206

Update Dockerfile and README for Chapel Release 1.21.0: Release Branch Only

Merge pull request chapel-lang#14114 from jhoole/set-intel-compiler-v…

…ersion

Set intel compiler version for XC x86_64 build to 16.0.3.210.

Trivial, not reviewed.

This is an early draft of the 1.20 release that did will in nightly t…

…esting

This is an early draft of the 1.20 release that did well in nightly t…

…esting

Merge pull request chapel-lang#12630 from soohoonchoi/RAD-956

Update Dockerfiles and README for Chapel Release 1.19.0: Release Branch Only

Tag 1.18.0

Tag 1.17.1

Tag 1.17.0

Tag 1.16.0