Release notes for WeBWorK 2.16

This article is under construction. Use the information herein with caution until this message is removed.

New Features

Essay grader features
MathJax 3
Should we advertise MathQuill here, even though it was in 2.15?
ADD_JS_FILE and ADD_CSS_FILE
Improved hardcopy of PGML problems
TikZ images in problems.
New macro parserGraphTool.pl for interactive graphing problems
"digits" tolType (needs explanation wherever tolerance in general is explained)
`random_prime` and `random_pairwise_coprime` macros
PGML can be used in set header files
MathObject: context classes can have aliases and alternates. (For example variable "X" could be an alias for "x".)
improvements in efficiency to PGstatisticsmacros.pl
explanation essays (ask for a regular answer, separately ask for an explanation essay, but the essay part can be globally disabled)
Rearrange presentation order for homework and quizzes on Homework Sets page
Achievements items need not be single-use

Should there be a section like this? For example:

Fixed bug when Gateway questions were not in sequential order
Fix bug where, for example, `Formula("-5/(-2 x)")` would display `5/2x` for its text string

Many third party javascript libraries (jquery, jquery-ui, mathjax, codemirror, etc.) are no longer packaged with WeBWorK. These libraries are now installed via npm:

Install npm from your package manager (Ubuntu: apt install npm CentOS/RHEL: yum install npm).
Use npm to install third party javascript:

  > cd /opt/webwork/webwork2/htdocs
  > npm install

WW 2.16 requires MathJax v3. Previous versions of WW required MathJax v2 that was installed at /opt/webwork/MathJax. WW 2.16 installs MathJax via npm, so if you are upgrading an existing WW installation you may safely delete /opt/webwork/MathJax.
The following perl packages will need to be installed
- HTTP::Async (on Ubuntu install the package libhttp-async-perl)
- CGI::Cookie (see https://github.com/openwebwork/webwork2/pull/1149)
- Archive::Zip (on Ubuntu install the package libarchive-zip-perl)
There have been some tweaks to localOverrides.conf.dist. If you have not done any customization to localOverrides.conf then you should consider replacing it with a new copy of localOverrides.conf.dist. If you have made customizations in localOverrides.conf, you should consider synchronizing them with the latest version of localOverrides.conf.dist.
The math4 theme has changed. If you use a custom theme, you may need to update your theme files to address these changes.
WeBWorK is currently not compatible with recent versions of the SQL::Abstract package, so avoid upgrading past version 1.8. WW is known to work with versions up to 1.87.
If you want to allow the use of the new PGtikz.pl macro, you will need to install imagemagick (Ubuntu: apt install imagemagick) and modify /etc/ImageMagick-6/policy.xml and change the line near the end of the file from

  <policy domain="coder" rights="none" pattern="PDF" />

to

  <policy domain="coder" rights="read" pattern="PDF" />

Some text has changed in the WeBWorK interface, so there are new entries that need to be translated into other languages.