pool.conf: always use the path from the config file

Previously we had cached a copy in Pool_role for no obvious reason.
Also, consolidate Pool_role and Pool_role_shared into Pool_role.

Signed-off-by: David Scott <dave.scott@citrix.com>
Delay reading pool.conf until after xapi.conf

This is important since xapi.conf includes the path to pool.conf

Signed-off-by: David Scott <dave.scott@citrix.com>
If not running on xen, discover memory from /proc/meminfo

Signed-off-by: David Scott <dave.scott@citrix.com>
If not running on xen, don't fail if we can't query the balloon driver

If there's no balloon driver, we assume the memory target = static_max

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #1730 from djs55/pool.conf

pool.conf: always use the path from the config file