docs: README update suggesting disablement of wordfence plugin to avoid delays

[noodnik2]

Avoiding Delays

For some time I've noticed that it's now taking between 10 to 20 seconds to respond to a page navigation from the browser on my Macbook, virtually making it unusable!

After a (WAY too!) lengthly investigation, I narrowed it down to processing that the WordFence plugin was doing, so the main change in this PR is to add a recommended step in the README of deactivating plugin(s) that aren't needed for the local use-cases (such as development, in which security software is not needed, etc.)

Utility Scripts

The README file was also updated to reference and describe recommended usages of one or both of two new utility
scripts added, for:

• Creating a new administrator account to login with in case the normal one doesn't work, and;
• Block outgoing e-mails which may be sent by the app (e.g., so as not to bother anyone due to development activities)