The new sip build system complies with pep 517 and
requires configuration by a standard pyproject.toml
file rather than running a single command. Along with
these changes the fixed sip.h file has been removed in
favour of a header generated locally if required.

We now support both the sip build systems as this is
required in our current support for multiple OSes. In
the process of adding support some cleanup has been
included:
  - the .sip files in our tree are now full module defs
    rather than the boilerplate being filled in by CMake,
    giving each module more flexibility.
  - the sipwrapper file has been removed in favour of a
    simpler script to simply strip the problematic code
    for C++17 compatability.

The workspace to be added is no longer necessary, because it appears
that calling afterReplaceHandle only slows the process while not doing
anything noticeable.

This commit thus simplify this, and thus quickens the execution of
replace_workspace by some 30%.

When using replaceWorkspace to replace the workspace being shown in an
instrument window using the python API, the user can specify the
new title of the window.
If none is specified, the name of the new workspace is used.

Add a sip function to allow the api user to replace the workspace
currently being shown on an instrument viewer window. This manage the
communication between the Python API and the C++ object and method.

Launch instrument view from context menu

Allows testing peaks overlay from vanilla Python

Defines a Python export wrapper for the C++ class
and a python base package to define other parts of the api
in future.