Collected small changes and fixes

[akohlmey]

Summary

This pull request combines multiple small fixes and changes

Related Issue(s)

fixes #3854

Author(s)

Axel Kohlmeyer, Temple U

Licensing

By submitting this pull request, I agree, that my contribution will be included in LAMMPS and redistributed under either the GNU General Public License version 2 (GPL v2) or the GNU Lesser General Public License version 2.1 (LGPL v2.1).

Backward Compatibility

No known issues.

Implementation Notes

The following individual changes are included:

• update VIM syntax highlighting for LAMMPS input files
• fix of an off-by-one bug when parsing the optional argument of the temper/npt command
• fixes to address static code analysis issues in selected files
• coding style improvement and code modernization in selected files
• small corrections and style improvements in the manual

Post Submission Checklist

• The feature or features in this pull request is complete
• Licensing information is complete
• Corresponding author information is complete
• The source code follows the LAMMPS formatting guidelines
• Suitable new documentation files and/or updates to the existing docs are included
• The added/updated documentation is integrated and tested with the documentation build system
• The feature has been verified to work with the conventional build system
• The feature has been verified to work with the CMake based build system
• Suitable tests have been added to the unittest tree.
• A package specific README file has been included or updated