cppkoans: added DontWarnAboutUnreferencedVars
gtets: Unshuffle could not handle the case that test_case_indicies_ is smaller than test_cases_
gtest: now the list of 'test part results' also contains successfull test parts

According to gtest's documentation that list should also contain successfull test parts, but apparently that was not the case. Made a clumpsy attempt to solve that problem. I fear this patch is neither runtime performant nor does it generically catch _all_ cases.
added koan area integer_types
booleans: added koan: sizeof(bool) is implementation-defined
ideas_and_todo: added ideas
added koan area pointers
added koan area expressions
finished rewording implementation-specfic to implementation-defined
change storage type of global identifiers ___... from static to extern
introduction.cpp: used wrong __...
strings: answer was non-__...
gtest: unneeded identifier implementation_defined within the expected expression is a failure

the identifier implementation_defined within the expected expression is a failure iff the actual expression is not implementation defined
characters: reformatted comments
introduction.cpp: added koan to teach type_info::name()'s return values
characters: fixed docu: char16_t / char32_t are no distinct types in C++, there is no 'unsigned/signed wchar_t'
arrays: extended