Customized run option

Pull request for feature which allows customization of script run options. Encapsulates some from these issues:
#32
#6
#5

Encapsulated in this pull request is:

1. Additional code to create variable options for current working directory, command arguments, and script arguments. These are saved per view.
2. `⌘-i` run will use these options, which by default revert to the current behavior that `⌘-i` has
3. `⌘-shift-i` runs `⌘-i`, then opens the options dialog where changes can be made to the options. These options persist through runs of `⌘-i` and `⌘-shift-i` for a particular window.

Todo

- [ ] Make the UI cleaner/more intuitive/easier. Perhaps some autosaving, collapsing the close/save into one button, ideas?
- [ ] Make the options persist past the lifetime of the view via the filesystem somehow
- [ ] Other stuff?