convert strings as well in capi_topointer and capi_tolightuserdata
move type and typename to take advantage of bounds checking
check that an argument is passed
new function isinteger
rename heavyuserdata to fulludata
rename lightuserdata to lightudata
more exact size test for size_t to lua_Integer
compile for Lua version
Lua >=5.3-specific strict tofloat function
additional type guard for Lua >=5.3 (introduction of integer type)
different way of calculating value is integer (in Lua <=5.2)
Lua version compatibility guards for 5.1
base lib is already on the stack