allow to configure custom shortener

[zhisme]

allow to configure custom shortener to not define every constant by hand

idea: is to put some constants list and feed it to shortener that will define himself those shorter version constants

# the default one
def shortener(klass_name)
  klass_name.to_s.gsub('::', '')
    .split(/[a-z]/).select { |lt| !lt.empty? }.join
end

shortener(MyClass)
# => MC
shortener(MyModule::MyClass)
# => MMMC
shortener(MyModule::MyModelsNamespace::Module)
# => MMNM