Improve isolation of tagged tests

[dataclouder]

• Improved tagged tests to make sure they can run in isolation
• Added a test to check tags isolation (runs with make test)
• added command make tagverify to run the tags isolation test

$ make tagverify
=== RUN TagsTest
  --- PASS: TagsTest/ALL
  --- PASS: TagsTest/api
  --- PASS: TagsTest/auth
  --- PASS: TagsTest/binary
  --- PASS: TagsTest/catalog
  --- PASS: TagsTest/disk
  --- PASS: TagsTest/extnetwork
  --- PASS: TagsTest/functional
  --- PASS: TagsTest/gateway
  --- PASS: TagsTest/lb
  --- PASS: TagsTest/lbAppProfile
  --- PASS: TagsTest/lbAppRule
  --- PASS: TagsTest/lbServerPool
  --- PASS: TagsTest/lbServiceMonitor
  --- PASS: TagsTest/lbVirtualServer
  --- PASS: TagsTest/network
  --- PASS: TagsTest/org
  --- PASS: TagsTest/query
  --- PASS: TagsTest/search
  --- PASS: TagsTest/user
  --- PASS: TagsTest/vapp
  --- PASS: TagsTest/vdc
  --- PASS: TagsTest/vm
--- PASS: TagsTest (48s)

(Also removed vcd_org_group duplicated line from CHANGELOG)

[vbauzys]

LGTM

[Didainius]

Thanks. It passes for me.