ItemResponseTrees 0.2.5

Fixed tests and vignette that failed due to changes in package mirt version 1.32.1.
augment() now consistently prefixes new columns with .fitted. or .se.fit.. Furthermore, its argument se.fit was renamed to se_fit (as recommended by package modeltests).
Uncoupled README from the vignette; README is now much shorter.
R (>= 3.6.0) is now required in alignment with the dependency mirt.

ItemResponseTrees 0.2.4 (2020-04-24)

Condition handling was refactored (e.g., myTryCatch() was replaced with simsalapar::tryCatch.W.E()).
sym_diff() was replaced with sets::set_symdiff(), and sort2() was removed.

Modified package Description field for CRAN
Modified vignette, install.packages was commented out.
Credit to Jackson for the jackson data and Dontas for sort2() is now given via appropriate attribution rather than usage of \author.

In the model syntax, the section Subtree is deprecated and was merged with section Constraints.
Long variable names are no longer automatically replaced. They are now accepted for mirt and TAM, but no longer for Mplus.
logit is now the default link function everywhere.
mirt is now the default engine in fit().

More complex models using constraints (that were only available for Mplus) are now implemented for mirt and TAM.
The new function irtree_create_template() helps to create a model string.
Data set jackson (Big Five questionnaire) was added.
Many internal changes to increase robustness.
Controlling features of the engine in fit() is now done via a single control argument (rather than ...), and helper functions control_<engine>() make that painless.
The documentation was improved.
The output of tidy() was enhanced (added columns parameter and component), and the argument par_type is now required for mirt.

Add wrapper functions for the TAM package
Add the multidimensional partial credit model (not an IR-tree model); works only in TAM