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Features:

• Add an initial Rust reimplementation of verify (#13)
• Add a man page (#19)
• Improve RPM spec file (#18, #22)
• Run tests at build-time (#39)
• Add Meson build system; the Autotools build system is still provided for now, but is intended to be removed in the next release (#43)

Bug fixes:

• Fix handling of submodules in subdirectories, particularly important for Meson subprojects (#36)
• Fix test failures (#39)
• Port Python implementation from Python 2 to Python 3 (#39)
• Fix error handling during iteration (#16)
• Give better messages if we fail to open a submodule (#16)
• Fix quoting issues and error handling in autogen.sh (#24)
• Fix deprecation warnings (#38, #42)