Refactor RuleFieldValidator into strategy classes
More precise error message for static MethodRules
Rename RuleFieldValidator to RuleMemberValidator
Allow static @Rule members if also @ClassRule
Merge pull request #932 from rowanhill/non-static-class-rules

Allow members annotated with both @ClassRule and @Rule to be static
Mentions that you need to create a branch
Update CONTRIBUTING.md
Fix compile