Update CBMC man page

[tautschnig]

With command-line help being complete, help2man was used to create an
updated list of options for CBMC's man page. Moving forward, automated
checks for man-page completeness will be put in place so that future
changes to the command line will have to be reflected as part of the
changing commit.

• Each commit message has a non-empty body, explaining why the change was made.
• Methods or procedures I have added are documented, following the guidelines provided in CODING_STANDARD.md.
• The feature or user visible behaviour I have added or modified has been documented in the User Guide in doc/cprover-manual/
• Regression or unit tests are included, or existing tests cover the modified code (in this case I have detailed which ones those are in the commit message).
• My commit message includes data points confirming performance improvements (if claimed).
• My PR is restricted to a single feature or bugfix.
• White-space or formatting changes outside the feature-related changed lines are in commits of their own.

[codecov]

Codecov Report

Base: 77.88% // Head: 77.88% // No change to project coverage 👍

Coverage data is based on head (2d183e5) compared to base (c764c1d).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #6937   +/-   ##
========================================
  Coverage    77.88%   77.88%           
========================================
  Files         1576     1576           
  Lines       181856   181856           
========================================
  Hits        141645   141645           
  Misses       40211    40211           

Impacted Files	Coverage Δ
src/util/expr.h	97.02% <ø> (ø)

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[NlightNFotis]

Is there some way to get the version here to be integrated with the one in src/config.inc? Maybe some sed magic before a new version? 🤔

[tautschnig]

If someone can educate me on how to accomplish this in CMake then I'd happily add this. I'd hope that https://cmake.org/cmake/help/latest/command/install.html#script could somehow work, but I'm not entirely sure when this is really run. @thomasspriggs perhaps?