Move existing flash methods into Flash component/helper
Add FlashComponent tests
Add FlashHelper tests
Add ability to pass exceptions as flash message
Move positional params into options array
Update flash tests for options array
Add call magic method for verbose calls with elements with flash_ prefix
Add docblocks to flash methods
Update flash plugin element docblock
Add flash_helper element
Rename FlashHelper's 'out' to 'render'
Inflect element name to underscore
Add description for FlashHelper class, fix typo in render() docblock
Use assertTag for flash_helper element tests
Remove flash string template and class option, update tests
Add escape option and test, remove leftover class option stuff
Remove component escaping, change FlashHelper attrs param to options
Remove test class teardown/setup and session clearing
Type hint options array param, use + operater for array merge, update docblocks
Fix FlashHelper render docblock typo