Added a first section  about classes and class names.

Also stuff about "constructors". Note that Sklyar's stuff is wrong.

Introduced macro \Q for textquotesingle so that code can be copy/pasted.
Commented out a couple of print statements.
Moved 2 files into the package.
Updated DESCRIPTION  (I thought I did that already!)
Added newline in chunk. Completed comment.

Removed some unnecessary linebreaks.
Bumped version, to make sure it was working.
After doing
    detach("package:CTDesignExplorer", unload=T)
    library("CTDesignExplorer")
the .onAttach greeting message appeared.
Wrote a message "Run createCTDEcatalog"
as a reminder... can't write into locked env.
Added threePlusThree_five_tiers.

Having moved createCTDEcatalog into the package, and running createCTDEcatalog(),
I still get
Error in assign(mname, def, where) :
  cannot add bindings to a locked environment
even though it's pos=1.
exporting createCTDEcatalog
In place of "assign", which fails in .onAttach due to locked environment,
I use local().  That works.

Whether assigning into the .GlobalEnv is the best thing, probably not in the long run.
Call patientToSTring instead of showAPatient, which was apparently hanging around in .GlobalEnv all this time!
Expand prototype for APlusBSpecifier, to include a default for TierDoses.
Added:

library(CTDesignExplorer)
createCTDEcatalog()
.gitignore update