- further fixes of inccorect overflow errors for int (and long on LLP64 systems) * prev commit had bugs * added overflow tests for also int, long, long long (for both, lp64 and llp64) - while at it, fixing a reference leak when not using python with utf8 caching

# TODO:
#  - how to handle C files? such as intutils.cpp and ldynguess.c
TOP=..
SRCS="typesignature.lua array.lua dynload.lua dyncall.lua dynport.lua path.lua"
luadoc -d "${TOP}/doc" ${SRCS}