accordion 2.4.0

An expandable Flutter widget list where each item can be expanded or collapsed simply by clicking on the header.

[2.4.0]

• merged PR from @anatolinicolae
• updated to latest versions of GetX & scroll_to_index
• increased maximum number of sections to 10,000

[2.3.0]

• merged PR from @jobic10 to make Key optional
• merged PR from @SirObi to allow multiple Accordion instances on one page
• added callbacks when opening/closing AccordionSections. Inspired by @singh-karan-7

[2.2.3]

• added some missing documentation

[2.2.2]

• fixed error when using multiple Accordion in a PageView

[2.2.1]

• fixed missing documentation
• fixed deprecated SingleGetTickerProviderMixin to GetSingleTickerProviderStateMixin

[2.2.0]

• code refactoring
• added headerBackgroundColorOpened as an option when a section is open. Default is headerBackgroundColor
• added sectionOpeningHapticFeedback and sectionClosingHapticFeedback to play a haptic feedback when opening/closing a section.
• added openAndCloseAnimation to Accordion to control if sections should animate when opened/closed.

[2.1.2]

• added disableScrolling prop to Accordion. Useful when the Accordion is used within a ListView or something else that already scrolls.

[2.1.1]

• fixed controller issue with scrollbar
• fixed problem with flipRightIconIfOpen
• fixed headerBorderRadius prop not reacting when set globally via Accordion
• added shrinkWrap and AlwaysScrollableScrollPhysics to the Accordion widget

[2.1.0]

• headerText, headerTextStyle, headerTextAlign have been removed -- please use header instead
• the content area now has a 1px border by default
• the background color of the header and the contentBorderColor share the same default color (primaryColor)

[2.0.1]

• included "Accordion within Accordion" in the example app (see notes in README)
• changed default borderRadius of header and content to 10
• updated documentation and example app

[2.0.0]

• deprecated headerText, headerTextStyle, headerTextAlign
• new parameter header which replaces all of the above

[1.0.4]

• changed line length to 80 for dartfmt

[1.0.3]

• fixed non-final values in AccordionSection
• changed default scrollIntoView animation to fast
• updated docs

[1.0.2]

• fixed Flutter SDK version

[1.0.1]

• fixed dependencies
• added null safety
• fixed static analysis problems
• fixed problem with dartdoc

[1.0.0]

• Initial release