Method names are in camel case - first cut

Change all classes under namespace amm::icon_search
Method names are in camel case - second cut

Change all classes under namespaces amm::representation & amm::transformer
Bring RepresentationInterface under amm::representation
Bring TransformerInterface under amm::transformer
Method names are in camel case - third cut

Change all classes under namespace amm::xdg
Mark constructors with single argument as explicit
Method names are in camel case - fourth cut

Change all classes under namespace amm
Mark constructors with single argument as explicit