Replace joda time with Java 8 DateTime API, close #92.
Refactoring: extract variable jacksonJsonMapperLibraries in build conf.
Remove Guave Joiner #95.
Remove Guava Joiner #95, fix tests.
Remove Guava immutable map #95.
Throw exception on duplicate keys for map.
Remove Guava Iterables usage #95.
Remove Guava Iterables usage #95.
Make requireNonEmpty return the value.
Fix Jackson JSON mapping problem with LocalizedString.
Make LocalizedString constructors private and replace Scala test class with Java test class.
Remove Guava ImmutableList usage #95.
Remove Guava newArrayList and newLinkedList usage #95.
Remove Guava Maps.newHashMap usage #95.
Replace CategoryTree spec in Scala with Java #95.
Remove Guava Objects class usage #95.
Remove Guava Srings class usage #95.
Remove Guava Resources class usage #95.
Remove SphereResultRawSpec, since the exception mechanism will be reworked anyway #95.
Remove SphereResultRaw, since the exception mechanism will be reworked anyway #95.