Giant copy from 4.2 for charting

This rips out some of the 4.0 copying and replaces with 4.2 copying.
It also no longer requires that you have ShowChart=1 in your URL to get
a chart, since 4.2 deals with that more gracefully.

This probably has bugs, and still doesn't port saved charts into the
RTIR search because I'd rather spend effort removing the RTIR specific
BaseQuery search stuff.

Documents that URLs with the old arguments aren't going to 'just work'
on 3.2, but since the charts are much better, you'll want to rework them
anyway.

Fixes issues #30262
Prevent Module::Install::RTx from clobbering README
Merge branch '3.2/charting-updates'
Fix up MANIFEST after merge