simple optimisation that statically maps keyword arguments to positional arguments when called signature is known

remove warning about missing 'const' support from docs and fix advice on declaring macros as 'enum' (which works only for ints)

Fix overflow_check CompileError with msvc

--HG--
extra : transplant_source : %3FH%B6t%1FFL%D8%2BF%7CV%7D%10T9%EA%CB%A0%00

enable control flow analysis for stack allocated structured variables (struct, union, array, C++ class)