This removal allows us to remove the `hdrs` target from every module; there
were only two modules that still used it, and they have both been fixed.

The purpose of this is to remove the dependency on tclx, a non-standard
package.

Synchronised all of the config files in configure/E3 and configure/modules in order to merge the two configuration directories.

remove inclusion of the run_iocsh script and change tests and targets accordingly; idea is that run-iocsh is a required package but not part of require per se