Renaming proposals

• NormalizedGaussian → NormalUnit
• _typefunc → _type_function
• nestedmkdict.child → nestedmkdict.make_child
• NodeBase._missing_input_handler -> NodeBase._input_strategy
• MissingInputFail -> InputStrategyBase;
• MissingInputAdd -> AddNewInput;
• MissingInputAddPair -> AddNewInputAddNewOutput
• MissingInputAddOne -> AddNewInputAddAndKeepSingleOutput
• MissingInputAddEach -> AddNewInputAddNewOutputForBlock
• MissingInputAddEachN -> AddNewInputAddNewOutputForNInputs