Additional polish on show methods

[eddelbuettel]

PR #342 is really good and gets us almost to the finish line of not relying on core code (to stdout) for object display and adding a numer of missing show() methods.

It tickled an error an real penguins data set (with NA values, as opposed to the cleansed one in cloud use) which I fixed that. While at it, I also made the code a little tighter and more idiomatic (and removed use of try). I apologise for the whitespace changes but I am quite used to how ESS typesets in base R defaults and this brings methods in further to the left.

Please have a look with your test arrays, it it is looking ok on the ones I tried.

(The last commit was needed or else one test on UINT32 would balk here. I am not sure how that didn't come up when we looked at the PR that brought it in. I should also have caught the use of tiledb_dense there which we try to phase out / will remove next month.)

[shortcut-integration]

This pull request has been linked to Shortcut Story #12282: Expand R-UDF validation coverage: make sure essential API calls work.

[eddelbuettel]

CI is failing on Windows due to network flakyness for the (forced) installation of qpdf(which we don't even use/need). On re-run one of three passes, will probably hit the re-run button again in an hour or so. It's all fine on Azure for the other two OS.

A re-run of CI at GitHub resolved the flakyness caused earlier by network / remote site issues.

[johnkerl]

Looks good to me -- thanks @eddelbuettel !!

[eddelbuettel]

My penny-dropping mechanism had a malfunction last week so I was overly slow in groking what you needed. Once I did it was just a question of suggesting a different touch here or there.