using namespace std
change math.h to cmath
add OPTIMIZE option
add return_sv macro
element access is changed to method access
fix ElementXS
change implementation to XS
change char* to SV*
fix bug character delete empty memory
fix double stringify bug
fix complex as_xxx bug
Revert "fix complex as_xxx bug"

This reverts commit 3d3db2c6f57041d019e3f80838a0c7abbd67ee1a.
rename create_double to new_double
add new_xxx functions
fix complex bug
fix element-inf.t
fix singleton bug
fix nan boolean test
fix all tests
fix ref condition