test

Polish XCTest filtering

Improve XCTestConventionPlugin test coverage on Windows

Rename SwiftTestExecutable to SwiftXCTestBinary

Remove SwiftBundle types from public API and collapse XCTests into one type

Merge `CreateSwiftBundle` task with `InstallXCTestBundle`

Fix CI failure regarding working directory on Linux

Add support for XCTest report generation on Linux

Add new cpp-unit-test plugin and base types

quasi-working google test task

Cleanup, javadoc and test fixing

Fix CI failures

Added `ObjectFactory.property(Class)` as a replacement for `ProviderFactory.property(Class)`. Changed all usages to use the new method.

Implement XCTest support for Linux

Fix task naming test failure

Merged `AbstractNativeCompileTask.objectFileDirectory` property into `objectFileDir`, changing its type to `DirectoryVar`. This is a breaking change.

Changed the XCTest plugin to use the project directory as the working directory for test execution, for consistency with the JVM tests.

Also wired in the `test` task as a dependency of `check` (and `build`).

Changed the XCTest plugin to honour changes to the build directory when generating reports.

Added `debuggable` flag to `AbstractLinkTask` and changed the C++ and Swift plugins to set this to `true` for the debug variants of each library, executable and test suite.

Changed the Visual C++ toolchain to understand this flag and add the appropriate linker arguments.

Changed the C++ and Swift plugins so that by default debuggable binaries are built for the debug variant, and non-debuggable optimized binaries are built for the release variant.

Added `debuggable` and `optimized` flags to `AbstractNativeCompileTask` and changed the tool chain implementation to generate the relevant compiler options. The C++ and Swift plugins set these flags on the compile tasks.

Also changed `AbstractNativeCompileTask` and `AbstractLinkTask` task types to provide default values for compiler args and macros (both empty) rather than forcing build logic to always set these.