Bump version
Enhance handling of non-null and non-empty fields especially in immutable beans

See #20
Merge branch 'origin/master'

Conflicts:
	src/changes/changes.xml
Handle extra spaces in definitions

Fixes #25
Refactor code generation avoiding two lines next to one another

Better approach to if statements
Add setting to allow immutable builders to be private

Fixes #26
Release v0.8.4