Use Rubocop

I think in general for generic yast style should be also:
```
# do not force %r
Style/RegexpLiteral:
 Enabled: false

Style/SignalException:
 EnforcedStyle: only_raise

Style/CaseIndentation:
 IndentWhenRelativeTo: end

# Do not allow and or or in conditionals
Style/AndOr:
 EnforcedStyle: conditionals

# ycp killer use aligned hash, so I think we can continue with its usage as it is really much better, especially in modules which heavily use hashes
Style/AlignHash:
 EnforcedHashRocketStyle: table
 EnforcedColonStyle: table

# We need to decide and this is easier to recognize in code
Style/AccessModifierIndentation:
 EnforcedStyle: outdent
```

Just parts from bootloader config, that I find useful and helpful.