feature/goto-definition-prompts-for-empty-scope

[kisp]

Hi,

I have a small change here for alchemist-goto-definition-at-point. If no scope can be found, i.e. if (alchemist-scope-expression) returns "", the user is prompted in the minibuffer.

The rationale for this is that sometimes I would like to jump to a definition that is not written somewhere in the current buffer. So instead of writing this into the buffer in order to be able to jump there, I would prefer to write it into the minibuffer.

Could you help to make this pull request even nicer?

• please comment on how I changed alchemist-goto--open-definition. Should I do something differently?
• Is there a way to ask for the definition in the minibuffer with completion support? I think this would be even better.