Sync with jdk9 and ASM alpha 2

[Remi Forax]

Hi Alan,
if i get it right, the jdk9 b148 (not the jigsaw version) get a refresh of module-info classfile format but did not get the last two changes,
version of requires and the two new constant pool entries.
Do you plan to push these changes in the jdk9 workspace soon so i will delay the release of ASM 6 alpha 2 or do you plan to introduce these changes later so i should release an alpha 2 now and release an alpha 3/beta later ?

regards,
Rémi