Validate only changed

[wwoytenko]

The changes are as follows:

• The validation command was rewritten almost from scratch. Now the code is much cleaner than before
• New option transformed-only - displays only bells that are transformed and PK
• JSON output format is different for --diff and without it
• The format parameter now controls the output type JSON or text
• Added the table-format parameter which is responsible for the vertical and horizontal table orientation
• Added the --warnings parameter, if it is specified then not only fatal-warnings will be displayed, but also those with a lower severity

1. Diff + json + transformed-only + warnings

greenmask --config config.yml validate --warnings --data --diff --format json --transformed-only

2. Similar to the previous one, but tabular output

greenmask --config config.yml validate --warnings --data --diff --format text --table-format vertical --transformed-only

3. Just validation that there are no errors in the config

greenmask --config config.yml validate

4. Printed only validation warnings

greenmask --config config.yml validate --warnings