Service broker settings include 'plan_updateable'

wip
Add acceptance test for plan upgrade
Bump src/cf-mysql-broker

Bump cloudfoundry/cf-mysql-broker:
  David Sabeti:
     Handle new error cases and backfill tests ( Travis Success: https://travis-ci.org/cloudfoundry/cf-mysql-broker/builds/39332418 )
  Ruth Byers and Raina Masand:
     Service broker allows updateable plans ( Travis Success: https://travis-ci.org/cloudfoundry/cf-mysql-broker/builds/38946316 )
Bump cf-mysql-broker
Merge branch 'master' into plan-upgrade-broker-wip

Conflicts:
	test/acceptance-tests/cf-mysql-service/p_mysql_test.go
Merge pull request #39 from cloudfoundry/plan-upgrade-broker-wip

Plan upgrade broker wip
Add browser tests, excluded from acceptance-tests errand by default.

[#79309104]
Comment out upgrade acceptance test

Most of our environments do not yet have a Runtime that supports the upgrade endpoint. Until they do, we need to keep this test commented out. As soon as the envs are ready, we can uncomment this and allow them to run
Update route-registrar so it writes its own pid

no more pgrep
Haproxy can be scaled and dashboard urls match haproxy indexes

default is 2 HAProxies
[#78082222]
avoid symlink for acceptance-tests
properly define cookie_secret
Merge pull request #41 from cppforlife/cookie_secret

properly define `cookie_secret` property