bubble

Added a border, a key. Changed Alignment to AlignmentGeometry.'

• Added a border (borderColor, borderWidth, borderUp).
• Changed Alignment to AlignmentGeometry.
• Added a key.

Null safety, BubbleNip.leftCenter, BubbleNip.rightCenter and showNip.

• Null safety!
• Added BubbleNip.leftCenter and BubbleNip.rightCenter. Since now the width for top/bottom and center is different you need ti use the showNip parameter instead of BubbleNip.no to remove the nip.

• Remake stick. If stick set to false, the right offset of bubble equal to the offset from the left, not taking into account the size of the nip. This allows the bubbles to line up. If stick set to true, the far side will be stick to the edge.
• Removed showNip. It's useless now.
• Corrected README.md and screenshots.

Fixed bug - don't draw a circle in the nip in leftBottom and `right…

• Fixed bug - don't draw a circle in the nip in leftBottom and rightBottom modes.

Fixed date of release in CHANGELOG.md

Merge branch 'master' of https://github.com/vi-k/bubble

• Fixed README.md.
• Added stick property.
• Changed NO, TOP_LEFT and TOP_RIGHT to no, leftTop, rightTop in BubbleNip.
• Added leftBottom and rightBottom to BubbleNip.
• Refactoring.

• Added additional properties similar to properties in style. They are priority.
• EdgeInsets replaced by class BubbleEdges. It similar to EdgeInsets, but default values are null. Thus, padding: BubbleEdges.only(top: 2) will only replace padding.top without affecting left, right and bottom.

• Wrote README.md.
• Made screenshots.

• Added an example.

• Published on https://pub.dev/.

• First release.