* Update Swift version used by SwiftFormat
* Update SwiftLint version
* Rely on new virtual 'all' rule in SwiftLint
* Enable SwiftLint rule 'direct_return' rule and fix all violations
* Enable SwiftLint rule 'shorthand_optional_binding' rule and fix all violations
* Enable SwiftLint rule 'blanket_disable_command' rule and fix all violations
This allows for a simpler setup and the usage of a recent version of Go. The library provides a build script which creates an XCFramework containing binaries for multiple target architectures. The gnu-dummy.patch is taken from mssun/gopenpgp. The forks are not needed anymore.
