- best possible fix for #189 to reenable https servers
- `UA Sample Client` and `UA Sample Server` expose https server. libuv.dll is by default for x64. Change
```
<PropertyGroup>
<RuntimeIdentifier>win7-x64</RuntimeIdentifier>
<BaseNuGetRuntimeIdentifier>win7-x64</BaseNuGetRuntimeIdentifier>
</PropertyGroup>
```
to win7-x86 if required.
- fix exception in https client when setting the Timeout
- fix travis build script for linux. kestrel server on ubuntu doesn't respond on ipv6Any ipaddress.
- fix a timing problem in the travis script.
2. Removed client cert validation from HTTPS client and server as this is not supported on all platforms, e.g. .Net4.6.
3. Reverted back to XmlDocument from XDocument as this is now supported via a NuGet package on UWP and XDocument is not supported on .Net4.6.
4. Baseline .Net4.6 samples and assoc. controls project check-in, not working yet.
5. Moved UWP client controls from SDK to Samples directly.