* bump macOS image on Azure CI to macos-11
##[warning]The macOS-10.15 environment is deprecated, consider switching to macos-11(macos-latest), macos-12 instead. For more details see https://github.com/actions/virtual-environments/issues/5583
* fix CI error
(cherry picked from commit 8ef509b85b)
* refactor all code that builds csources
* fixup
* nim_csourcesDir_v0 + nim_csourcesDir
* remove deprecated, unused scripts from ci/
* reuse nimCsourcesHash in ci
* simplify CI pipelines by reusing nimBuildCsourcesIfNeeded
* simplify ci_docs.yml by reusing nimBuildCsourcesIfNeeded
* cleanup
* use csources_v1 as destination dir
* fixup
* remove pushCsources
* address comment: remove build.sh support for now
* fixup
* support skip ci in azure pipelines
* [skip ci] example of a commit that skips CI
* example of a commit that does not skip CI
* fix github actions logic for ci skip handling
* [skip ci] example of a commit that skips CI for all pipelines
* example of a commit that does not skip CI for any pipeline
* use NIM_TESTAMENT_BATCH for important_packages, improve formatting, code cleanups
* workaround for nimcrypto not having `--path:.`; remove workaround "two are special snowflakes"
* add comment explaining why nimcrypto fails and what packages need to be testable
* Enable fidget in important_packages.
Fidget now works with `nimble test` and there is a CI: https://github.com/treeform/fidget/commits/master
* Add libx11-dev to make fidget compile.
* try libxcursor-dev
* try xorg-dev