add system requirements.
Update README.md
Merge pull request #2 from myui/hotfixes

Hotfixes
add define-all.hive.
Merge branch 'master' of https://github.com/myui/hivemall.git
Merge pull request #3 from myui/hotfixes

Hotfixes - added define-all.hive
changed the directory structure.
Merge pull request #4 from myui/hotfixes

changed the directory structure.
Merge remote-tracking branch 'origin/master' into develop