Add an attribute to identify and communicate deprecated REST endpoint calls

[Brian Lewis]

Develop [Deprecated] attribute that will add a custom header X-Deprecated to the response.

This will assist in the tidy-up of names in #949

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[Brian Lewis]

feat(warehouse): attribute to add X-Deprecated header to communicate deprecated API

Resolves #950

→ <<cset be7c932e8ad0>>

[Brian Lewis]

Deprecations reported to the client are now displayed in the console:

When Deprecation Response is ‘Continue’ the deprecated call has Status = 200 and the console message is a Warning.

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When DeprecatedResponse = RaiseError Status = 410 (Gone) and the console message is an error:

        [HttpGet]
        [Deprecated("api/warehouse/teachers?report", DeprecationResponse.RaiseError)]
        [Deflatable]
        [Route("teachercount")]         // use 
        public object TeacherCount()
        {
            IDataResult ds = Ds.TeacherCount();
            return ds.ResultSet;
        }

‌

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[Brian Lewis]

feat(warehouse): display deprecation warning/error in browser console

Resolves #950

→ <<cset 6e3cdfa4a8b0>>