Sequence form "*Editor" components should dispatch an event rather than invoke a callback setInEditor

[duranb]

Currently the sequence editor's form components invoke a function that's passed in from the parent to affect some state on the parent. The convention that's easier to manage is to instead dispatch events up to the parent component. IMO, the only time that passing in a function is appropriate is if the parent needs to define some functionality for the child component to utilize within.