Separate client and daemon info in docker system info

Right now the only client side info we have is whether debug is enabled, but we
expect more in the future.

We also preemptively prepare for the possibility of multiple errors when
gathering both daemon and client info.

Signed-off-by: Ian Campbell <ijc@docker.com>

docs/reference/commandline/info.md

@@ -55,7 +55,12 @@ information about the `devicemapper` storage driver is shown:
 
 ```bash
 $ docker info
+Client
+------
+Debug Mode: false
 
+Server
+------
 Containers: 14
  Running: 3
  Paused: 1
@@ -96,8 +101,7 @@ Total Memory: 991.7 MiB
 Name: ip-172-30-0-91.ec2.internal
 ID: I54V:OLXT:HVMM:TPKO:JPHQ:CQCD:JNLC:O3BZ:4ZVJ:43XJ:PFHZ:6N2S
 Docker Root Dir: /var/lib/docker
-Debug mode (client): false
-Debug mode (server): false
+Debug Mode: false
 Username: gordontheturtle
 Registry: https://index.docker.io/v1/
 Insecure registries:
@@ -112,7 +116,12 @@ storage driver and a node that is part of a 2-node swarm:
 
 ```bash
 $ docker -D info
+Client
+------
+Debug Mode: true
 
+Server
+------
 Containers: 14
  Running: 3
  Paused: 1
@@ -168,8 +177,7 @@ Total Memory: 1.937 GiB
 Name: ubuntu
 ID: H52R:7ZR6:EIIA:76JG:ORIY:BVKF:GSFU:HNPG:B5MK:APSC:SZ3Q:N326
 Docker Root Dir: /var/lib/docker
-Debug Mode (client): true
-Debug Mode (server): true
+Debug Mode: true
  File Descriptors: 30
  Goroutines: 123
  System Time: 2016-11-12T17:24:37.955404361-08:00
@@ -209,7 +217,12 @@ Here is a sample output for a daemon running on Windows Server 2016:
 
 ```none
 E:\docker>docker info
+Client
+------
+Debug Mode: false
 
+Server
+------
 Containers: 1
  Running: 0
  Paused: 0
@@ -233,8 +246,7 @@ Total Memory: 3.999 GiB
 Name: WIN-V0V70C0LU5P
 ID: NYMS:B5VK:UMSL:FVDZ:EWB5:FKVK:LPFL:FJMQ:H6FT:BZJ6:L2TD:XH62
 Docker Root Dir: C:\control
-Debug Mode (client): false
-Debug Mode (server): false
+Debug Mode: false
 Registry: https://index.docker.io/v1/
 Insecure Registries:
  127.0.0.0/8