Hotfix crash in row, column extensions

[0.1.1] - 18/05/2020

• Hotfix: default value for main, cross axis alignment for row, column extensions.

Added basic set of extensions

[0.1.0] - 18/05/2020

• First usagable release of widgetx package.
• Added layout extensions for container, rows, columns
• Added text, list, align extensions.
• Still too early to be used in production apps.

Release readme updates to the project

• Updated readme with raw image path on github.
• Updated wip note, highly experimental state at the moment.

Initial release

• First nightly draft of widgetx extensions