fix (+ int big), when int is minus
fix (+ int big), when int is minus

aginika/EusLisp,bmagyar/EusLisp,wkentaro/EusLisp,wkentaro/EusLisp,bmagyar/EusLisp,bmagyar/EusLisp,wkentaro/EusLisp,wkentaro/EusLisp,aginika/EusLisp,bmagyar/EusLisp,aginika/EusLisp,aginika/EusLisp