Update content to reflect changes introduced in ess-require releases

[anderslindho]

Require 3.2.0 and 3.3.0 introduces a few major changes.

• all modules are now lowercased for consistency (e..g iocstats instead of iocStats) (technically not a change to require)
• module pinning is no longer required; startup scripts can require <module> instead of needing to require <module>, <version> (3.2.0)
• debuggers are called on by using iocsh.bash with flags dg (for gdb) and dv (for valgrind) (3.2.0)
• versions are now parsed as MAJOR.MINOR.PATCH-BUILD, with build number being optional, assumed to be zero if not present (3.3.0)
• the introduction of a local install command cellinstall which can be used together with a network mounted e3 build (3.3.0)
• the addition of a prebuild target (make prebuild) (3.3.0)
• a debug target (make debug) can now be called on before building (3.3.0)

For full release notes, see https://confluence.esss.lu.se/x/iBHFF