Don't repeat relaxed names that already showed up
Add FileEncodingApplicationContextInitializer

Looks for spring.mandatory_file_encoding and matches it against
System.getProperty("file.encoding").

Fixes gh-46
Allow relaxed names to include prefixes
Fix bug in RelaxedPropertyResolver with prefix ending in separator

E.g. with a prefix spring.jpa.hibernate. we want naming-strategy and
namingstrategy to be resolvable. It wasn't working before this change
because the whole property path was being manipulated, where you
actually need to manipulate the prefix and suffix separately.