Refactor Settings dialogs into separate component

Since the dialog is essentially reused for all of the different unit types, put it into its own component.

Have the inputted model items be an array of two elements: the first value is the actual value the settings should be set to, and the second is the string to display to the user.

This partially helps with #53, as it specifies the setting strings to be stored as non-i18n()-ed values. I did not test the code with a language other than English for this, and it might break the settings of users with a different language.