organise imports

Signed-off-by: Ferry Huberts <ferry.huberts@pelagic.nl>
suppress some 'unused' warnings

Signed-off-by: Ferry Huberts <ferry.huberts@pelagic.nl>
remove some unused private methods

Signed-off-by: Ferry Huberts <ferry.huberts@pelagic.nl>
remove some unneeded annotations

Signed-off-by: Ferry Huberts <ferry.huberts@pelagic.nl>