Set up rubocop
Unused local variables.
Use safe assignment in block conditionals
Don't assign variables in line-trailing conditionals.
Don't multi-line assign in block level conditionals
Handle long method warnings.

I'd like to set the max method length even shorter (25 lines),
but this creates the need for much refactoring. For now, I've set it to
50 lines, and have silenced the warnings on longer methods.
Disable the end alignment check.
Always have a space after a comma.
Don't nest ternary operators.
Document the rationale for the differences from the rubocop standard config.
Handle warnings about methods with too many parameters.
Limit line lengths to 100 characters.
Always have a space around math operators.
Spaces should be around = for default parameters.
Get rid of some empty lines.
Comments must have a leading space.
Keep a blank line before and after each public, private, and protected declaration.
Align array literals.
Prefer && over and.
Align ends of block with the start of the expression.