FMSLogo Code

Remove logic associated with abbreviations.xml.
This abbreviations.xml was removed long ago.
Abbreviations for a procedure are now documented with that procedure.

Add some comments to explain warnings about bad linkends

Minor improvements to documentation for PLLIST
- Clarify that the third list of a contents list are names of plists.
- Split the examples into two listings, since they are independent.
- Lowercase the names of the example plists to adhere to the style guide.

Improve formatting of QUEUE documentation:
- Remove a badly placed paragraph break
- Markup "value" as <parameter> to show that it's a name, not a noun.

Remove the exception for HOSTS for command-netconnecton.xml
This word no longer appears in the documentation for NETCONNECTON.

Remove TODO as an "all-caps" exception for some network commands.
I don't remember what was to be done, but "TODO" no longer appears in documentation, so it's not needed as an exception.

Change variable names "foo" and "bar" to lowercase, per style guidelines.

Minor fixes:
- Remove hard-coded exception for LOGOEXE.
This is now handled with a data-driven approach.
- Fix typo in banner comment
- Remove blank line

Fix typo in documentation for UNTRACE
"not being trace" -> "not being traced"

Re-add the suggestion to develop networking programs using "localhost".
This had been commented out because FMSLogo didn't support listening on the loopback adapter until version 7.0.0.