Move all core packages to root vapors prefix

• Move all com.rallyhealth.vapors.core code to com.rallyhealth.vapors for simplicity
• Left behind value and type aliases for main things

Add valuesOfType operation

• Add valuesOfType operation for getting all the facts of a given type and selecting the .value field from them

Publish to Sonatype / Maven Central

• Publish to Sonatype / Maven Central instead of Bintray
• Remove all deprecated methods and types from previous versions