Documented the console environment variables
Fixed some errors in the explanation
Minor grammar fix
More grammar fixes
Rewordings and transformed a list into a definition list
More tweaks and grammar fixes
Fixes and tweaks
feature #4665 Documented the console environment variables (javiereguiluz)

This PR was merged into the 2.3 branch.

Discussion
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Documented the console environment variables

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes
| Applies to    | all
| Fixed tickets | #4162

Commits
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df2a0f2 Fixes and tweaks
dd8157f More tweaks and grammar fixes
2fb082d Rewordings and transformed a list into a definition list
a1d88d8 More grammar fixes
8ead4a4 Minor grammar fix
6fc8f4c Fixed some errors in the explanation
7c4cd17 Documented the console environment variables