Merge branch 'jl/nor-or-nand-and'

Eradicate mistaken use of "nor" (that is, essentially "nor" used
not in "neither A nor B" ;-)) from in-code comments, command output
strings, and documentations.

* jl/nor-or-nand-and:
  code and test: fix misuses of "nor"
  comments: fix misuses of "nor"
  contrib: fix misuses of "nor"
  Documentation: fix misuses of "nor"

Documentation/CodingGuidelines

@@ -91,13 +91,13 @@ For shell scripts specifically (not exhaustive):
    E.g.: my_function () {
 
  - As to use of grep, stick to a subset of BRE (namely, no \{m,n\},
-   [::], [==], nor [..]) for portability.
+   [::], [==], or [..]) for portability.
 
    - We do not use \{m,n\};
 
    - We do not use -E;
 
-   - We do not use ? nor + (which are \{0,1\} and \{1,\}
+   - We do not use ? or + (which are \{0,1\} and \{1,\}
      respectively in BRE) but that goes without saying as these
      are ERE elements not BRE (note that \? and \+ are not even part
      of BRE -- making them accessible from BRE is a GNU extension).