Feat: Project admin menu

[chengfang-blutui]

This PR adds the menus resource to the project admin API and project public API.

Available pubic API methods:

blutui.project('foo').menus.list()
blutui.project('foo').menus.get('id')

Available admin API methods:

blutui.project('foo').admin.menus.list()
blutui.project('foo').admin.menus.get('id')
blutui.project('foo').admin.menus.create({"name": "primary menu", "handle": "primary-menu"})
blutui.project('foo').admin.menus.update('id', {"name": "primary menu updated", "handle": "primary-menu-updated"})
blutui.project('foo').admin.menus.remove('id')