Expose available_disk in stager advertisement
Add a way to wait for all parallel promises to complete

The problem doesn't appear until you start mixing threads (EM) and Fibers.
Merge remote-tracking branch 'origin/pr/117'
Dealing with arrays containing nil values gracefully

Signed-off-by: Phan Le <ple@pivotallabs.com>
Merge remote-tracking branch 'origin/pr/120'

Signed-off-by: Abhijit Hiremagalur <abhi@pivotallabs.com>
Handle services without credentials more gracefully

[#69197868]

Signed-off-by: Phan Le <ple@pivotallabs.com>
Merging cloudfoundry/dea_ng commit f341824 (cf-release v169).
Fix Windows tests to be drive-letter agnostic.