Add overloads of Select and Then for continuation actions
Use Select and Then in additional locations where appropriate
Update TestHelpers to show request headers as well as response headers
Allow providers to override the ContentType property (fixes #372)
Merge pull request #373 from sharwell/fix-372

Allow providers to override the ContentType property (fixes #372)
Merge pull request #374 from sharwell/SelectThen

Extend supported use cases for Select and Then extensions
Merge pull request #375 from sharwell/TestsShowRequestHeaders

Update TestHelpers to show request headers as well as response headers
Fix documentation reference not resolving
Fix _diskConfiguration field assignment
Merge pull request #376 from sharwell/MinorIssues

Minor issues