Slack for PHP v2.0.0 Release Notes

    • ignore phpunit.xml & rename to phpunit.xml.dist fix #16
    • exclude 'tests' & 'vendor' from calc code coverage. closes #18
    • code style rules; add .editorconfig
    • migrate to phpunit 6.5. closes #7. & Update PhpUnit to 7.5. Closes #27
    • migrate to mockery 1.0. closes #19
    • drop support for php 5, 7.0 & hhvm (fixes builds)
    • php docblocks for tests. closes #8
    • decrease Attachment::__contruct() complexity. closes #9
    • rename attributes to options
    • decrease Client::__construct() complexity. closes #12
    • Added response_type to allow for 'in_channel' vs 'emphemeral' messages in channel
    • Blocks support (Integrate Blocks with main Message/Client) by @cmbuckley:
      • Button element and Confirmation object
      • Checkboxes element and Option object
      • DatePicker element
      • Image element
      • Overflow element
      • TextInput element
      • RadioButtons element
      • Select element and OptionGroup object
      • MultiSelect element
      • Actions block
      • Context block
      • Divider block
      • File block
      • Image block
      • Input block
    • Fix php doc-blocks. Closes #39.
    • correct initial option check (fixes #40)
    • add travis notification to Slack. Closes #17.
    • fix class name. fix #45
    • Improve test coverage for Block kit
    • Added callback_id to Attachment.php (#50) to allow for working with the interactivity callback api in slack
    • bugfix: prevent call on non-object
    • Update Composer and PHPUnit to PHP 8.0 (#56)
    • reuse Payload for fillProperties() (decrease complexity). resolves #13
    • decouple Message from Client. Closes #15, fixes maknz/slack#70