Updates query to limit results in subquery for MySql according to U4-2329 Browsing Media Slow in 6.1.1
Fixes U4-2397 IContent Properties added with incorrect Value when read from Cache, and adds unit test for verifying types saved and returned for 24 standard DataTypes.
Fixes issue relating to the fix for U4-2589 where we need to clear the published db flag for previous versions when creating a new published version.
Fixes U4-2618 PDF indexer does not ensure spaces are added to textual content and fixes med trust compat relating to U4-2180 Problem with Examine MultiIndexSearcher after upgrading from 4.11.3 to 4.11.8
Updated to latest Examine version (contains bug fix for U4-2180 Problem with Examine MultiIndexSearcher after upgrading from 4.11.3 to 4.11.8) and removes the partially trusted callers attribute from the PDF lib because itextsharp by default doesn't support med trust.
Merge remote-tracking branch 'origin/6.1.4' into 7.0.0

Conflicts:
	src/Umbraco.Core/StringExtensions.cs
	src/Umbraco.Tests/Models/ContentExtensionsTests.cs
	src/Umbraco.Tests/TestHelpers/Entities/MockedContentTypes.cs
	src/Umbraco.Tests/Umbraco.Tests.csproj
	src/Umbraco.Tests/packages.config
removed test examine settings