[XLS-678] Add unit test coverage of Value/DataUtils.toString and add toSimpleString form

Reviewed-by: Stephen Colebourne
[XLS-676,XLS-678] Generate client strings via a context service

This will allow client bindings to customize the behaviour from the "toSimpleString" default.
Reviewed-by: Stephen Colebourne
[XLS-676] Gather all Value/Data toString logic into ClientMessageStrings

Reviewed-by: Stephen Colebourne
[XLS-676,XLS-678] Document existing methods, add test coverage, remove anything inappropriate that's not used, deprecate anything that's inappropriate but is used

Reviewed-by: Stephen Colebourne
[PLAT-4058] Exclude generated files from coverage report

Reviewed-by: Stephen Colebourne
[XLS-676] Improve hooks for sub-classes

Reviewed-by: Stephen Colebourne
[XLS-678] Adjust simple text to look better when used as part of longer exception strings

Reviewed-by: Stephen Colebourne
[XLS-664] Report the version of the host process of the "viewProcessor" component to native code

Reviewed-by: Stephen Colebourne
[XLS-678] Fix unit test errors from previous commit