iSEG Open Source v1.2.1

What's Changed

• merge fixes by @dyollb in #116
• Fix/forgiving hdf5 reader by @dyollb in #117
• fix macos build with clang 12.0 by @dyollb in #118
• Property widget by @dyollb in #119
• Improve "spherize", carve from outside function by @dyollb in #120
• add github action to build and test by @dyollb in #122
• Fix mask source, minor changes by @dyollb in #123
• Fix update progressinfo from thread by @dyollb in #124
• Kill qt3 by @dyollb in #126
• Extend cli for import by @mguidon in #127
• Add documentation for docker builds by @mguidon in #128

Full Changelog: v1.2...v1.2.1