acu123016 - [block_device] Find default ephemeral mount point for azure
by checking fstab entry
acu123016 - [block_device] Use mount command to determine the ephemeral
mount point
acu123016 - [block_devie] Update ephemeral mount point only if it is
already mounted in azure
acu123016 - [block_device] Don't try to delete /mnt or /mnt/ephemeral on
azure
Merge pull request #432 from rightscale/white_14_01_acu123016_fix_ephemeral_azure

White 14 01 acu123016 fix ephemeral azure