tests: Add tests for compile/run tcc.c with tcc -b then compile tcc.c again, then run tcctest.c

Just like with test[123] add their test[123]b variants. After previous 3
patchs all test pass here on Debian GNU/Linux on i385 with gcc-4.7 with
or without memory randomization turned on.

.gitignore

@@ -11,8 +11,11 @@ tc1.c
 error.c
 i386-gen1.c
 test.out1
+test.out1b
 test.out2
+test.out2b
 test.out3
+test.out3b
 web.sh
 memdebug.c
 bench