Introduce docc documentation and "supported features" #767

Job	Run time
Documentation check (6.1.2, jammy, corretto)	20s
Test (Java) (macos swift:6.1.2 jdk:corretto)	1s
Test (Swift) (macos swift:6.1.2 jdk:corretto)	1s
Test (Java) (jammy swift:6.1.2 jdk:corretto)	2m 40s
Test (Swift) (jammy swift:6.1.2 jdk:corretto)	4m 39s
Sample JavaDependencySampleApp (jammy swift:6.1.2 jdk:corretto)	5m 39s
Sample JavaSieve (jammy swift:6.1.2 jdk:corretto)	47s
Sample JavaProbablyPrime (jammy swift:6.1.2 jdk:corretto)	3m 19s
Sample SwiftAndJavaJarSampleLib (jammy swift:6.1.2 jdk:corretto)	4m 30s
Sample SwiftKitSampleApp (jammy swift:6.1.2 jdk:corretto)	5m 55s
Benchmark (JMH) (jammy swift:6.1.2 jdk:corretto)	7m 7s
Sample JavaKitSampleApp (jammy swift:6.1.2 jdk:corretto)	3m 35s
Sample JExtractJNISampleApp (jammy swift:6.1.2 jdk:corretto)	5m 34s
Sample JavaKitSampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample JavaDependencySampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample JavaProbablyPrime (macos swift:6.1.2 jdk:corretto)	1s
Sample JavaSieve (macos swift:6.1.2 jdk:corretto)	1s
Sample SwiftKitSampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample JExtractJNISampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample SwiftAndJavaJarSampleLib (macos swift:6.1.2 jdk:corretto)	1s
soundness / Unacceptable language check	5s
soundness / Broken symlinks check	3s
soundness / License headers check	6s
soundness / Format check	0s
soundness / Documentation check	0s
soundness / API breakage check	0s
soundness / YAML lint check	3s
soundness / Python lint check	7s
soundness / Shell check	32s
	45m 10s

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