v0.2.1

Release after implementing argument parsing from config files / command line.

What's Changed

• Argument parser by @clatlan in #183
• update comments relative to spec files by @carnisj in #198
• Bug: use the correct key for the config file by @carnisj in #200
• Update CONTRIBUTING.md by @carnisj in #201
• open the pop-up window in data_dir if specified by @carnisj in #202
• Gui dev by @DSimonne in #199
• Update the parameter "Linearity_function" by @carnisj in #203
• add support in preprocessing for 34ID-C by @carnisj in #204
• return the transformation matrix from the detector frame to the laboratory frame by @carnisj in #208
• Add task in doit to check broken links in the doc by @carnisj in #211
• Implement the chi circle for 34ID-C by @carnisj in #205
• Load positions from the log file when available (Lazy user) by @carnisj in #214

Full Changelog: v0.1.7...v0.2.1