Laundry list of things to check based on editing the developer documents in bes/docs

[jgallagher59701]

• The key BES.ServerUnixSocket should be set to the full path of your UNIX socket file. A common choice is /tmp/opendap.socket. This can also be overridden from the command line using the -u option to besctl.
• We provide a script that generates code that will compile immediately. It creates the source files you will extend, along with configuration files and makefiles. See besCreateModule in bes/bin which is 'built' by make and installed in $prefix/bin by make install.
• In the above, no DAP4 responses are mentioned.
• Should we delete the above 'templates' stuff?
• It seems like there's a certain amount of info duplication between the docs/BES_Overview (+ the rest of the docs) plus the README.md. We might want to consider removing all info from the README that is documented elsewhere, and linking to the docs directly---that would yield single sources of truth, plus make it easier to not have them go out of sync.