ServiceEnableTagOverride temporarily false after updating tags via catalog

Client: `0.7.0`
Server: `0.7.0`
### `consul info` for both Client and Server

Client:

```
agent:
check_monitors = 0
check_ttls = 0
checks = 40
services = 40
build:
prerelease =
revision = 'a189091
version = 0.7.0
consul:
known_servers = 3
server = false
runtime:
arch = amd64
cpu_count = 24
goroutines = 75
max_procs = 24
os = linux
version = go1.6.3
serf_lan:
encrypted = false
event_queue = 0
event_time = 1322
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 203710
members = 16
query_queue = 0
query_time = 1848
```

Server:

```
agent:
check_monitors = 0
check_ttls = 0
checks = 1
services = 2
build:
prerelease =
revision = 'a189091
version = 0.7.0
consul:
bootstrap = false
known_datacenters = 23
leader = false
leader_addr = 10.28.188.52:8300
server = true
raft:
applied_index = 25315303
commit_index = 25315303
fsm_pending = 0
last_contact = 67.123638ms
last_log_index = 25315303
last_log_term = 1511
last_snapshot_index = 25309666
last_snapshot_term = 1511
latest_configuration = [{Suffrage:Voter ID:10.28.188.52:8300 Address:10.28.188.52:8300} {Suffrage:Voter ID:10.28.188.51:8300 Address:10.28.188.51:8300} {Suffrage:Voter ID:10.28.188.57:8300 Address:10.28.188.57:8300}]
latest_configuration_index = 24077016
num_peers = 2
protocol_version = 1
protocol_version_max = 3
protocol_version_min = 0
snapshot_version_max = 1
snapshot_version_min = 0
state = Follower
term = 1511
runtime:
arch = amd64
cpu_count = 2
goroutines = 1413
max_procs = 2
os = linux
version = go1.6.3
serf_lan:
encrypted = false
event_queue = 0
event_time = 1322
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 203687
members = 16
query_queue = 0
query_time = 1848
serf_wan:
encrypted = false
event_queue = 0
event_time = 1
failed = 0
health_score = 0
intent_queue = 0
left = 0
member_time = 1270
members = 103
query_queue = 0
query_time = 1
```
### Operating system and Environment details

CentOS Linux release 7.1.1503 (Core)
### Description of the Issue (and unexpected/desired result)
- ServiceEnableTagOverride is set true
- When updating tags via the catalog ServiceEnableTagOverride becomes false, until presumably the agent syncs, even when EnableTagOverride: true is set in the payload to the catalog.
- Can't update again until ServiceEnableTagOverride becomes true
### Reproduction steps
- Create service
- Update tags
- Try to update tags immediately after, get rejected.

Start by reproducing the catalog service update sequence described: create a service, update its tags, and immediately attempt a second update. Trace the catalog update path involving ServiceEnableTagOverride and EnableTagOverride; done means tag updates are not rejected during the temporary false state.

Written by the indexing model from the issue text.