Use more STL like names: my_class instead of MyClass.

Use more STL like names: my_class instead of MyClass.
* data/lalr1.cc (LocationStack, LocationType, RhsNumberType)
(SemanticStack, SemanticType, StateStack, StateType)
(TokenNumberType, Stack, Slice, Traits, Parser::location)
(Parser::value): Rename as...
(location_stack, location_type, rhs_number_type, semantic_stack)
(semantic_type, state_stack, state_type, token_number_type, stack)
(slice, traits, parser::yylloc, parser::yylval): these.
* tests/calc.at, tests/regression.at, tests/actions.at: Adjust.