Add function logs support (#53) (#131)

Add function log aggregation and persistence using Fluentd and InfluxDB.

Fluentd and a helper sidecar run as a daemonset.  The poolmgr sets up logging for each function pod, using the helper sidecar. Fluentd forwards logs to InfluxDB, which is run as a deployment and service. The client CLI directly queries InfluxDB for logs.

Fluentd supports many outputs besides InfluxDB, so we aren't very tied to InfluxDB.

The setup is somewhat manual, which we should be able to improve by integrating this into the helm chart.

Diagram of component interactions: https://cloud.githubusercontent.com/assets/202578/23100399/b0e3ea00-f6ba-11e6-8f2f-6588cfef2e84.png

glide.lock

@@ -1,5 +1,5 @@
-hash: fb2f38693c5f2fade3db9434c266743d0f9ea9b5f878b44e79763e248136dcf2
-updated: 2016-11-14T01:06:12.764919869-08:00
+hash: 6b4c050c1cd5a7cbb99141348020c882d088b30a9fe9cf92b78a7f706e59da4c
+updated: 2017-02-22T23:15:19.862789385+08:00
 imports:
 - name: github.com/blang/semver
   version: 60ec3488bfea7cca02b021d106d9911120d25fe9
@@ -69,9 +69,15 @@ imports:
 - name: github.com/gorilla/context
   version: 08b5f424b9271eedf6f9f0ce86cb9396ed337a42
 - name: github.com/gorilla/handlers
-  version: ee54c7b44cab12289237fb8631314790076e728b
+  version: 3a5767ca75ece5f7f1440b1d16975247f8d8b221
 - name: github.com/gorilla/mux
-  version: 0eeaf8392f5b04950925b8a69fe70f110fa7cbfc
+  version: 392c28fe23e1c45ddba891b0320b3b5df220beea
+- name: github.com/influxdata/influxdb
+  version: b7bb7e8359642b6e071735b50ae41f5eb343fd42
+  subpackages:
+  - client/v2
+  - models
+  - pkg/escape
 - name: github.com/jonboulle/clockwork
   version: 2eee05ed794112d45db504eb05aa693efd2b8b09
 - name: github.com/juju/ratelimit
@@ -91,7 +97,7 @@ imports:
 - name: github.com/satori/go.uuid
   version: 879c5887cd475cd7864858769793b2ceb0d44feb
 - name: github.com/Sirupsen/logrus
-  version: d26492970760ca5d33129d2d799e34be5c4782eb
+  version: c078b1e43f58d563c74cebe63c85789e76ddb627
 - name: github.com/spf13/pflag
   version: 08b1a584251b5b62f458943640fc8ebd4d50aaa5
 - name: github.com/ugorji/go
@@ -99,7 +105,7 @@ imports:
   subpackages:
   - codec
 - name: github.com/urfave/cli
-  version: a14d7d367bc02b1f57d88de97926727f2d936387
+  version: 0bdeddeeb0f650497d603c4ad7b20cfe685682f6
 - name: golang.org/x/net
   version: 6acef71eb69611914f7a30939ea9f6e194c78172
   subpackages:
@@ -158,13 +164,6 @@ imports:
 - name: k8s.io/client-go
   version: 843f7c4f28b1f647f664f883697107d5c02c5acc
   subpackages:
-  - 1.4/kubernetes
-  - 1.4/pkg/api
-  - 1.4/pkg/api/v1
-  - 1.4/pkg/apis/extensions/v1beta1
-  - 1.4/pkg/labels
-  - 1.4/pkg/util/intstr
-  - 1.4/rest
   - 1.5/discovery
   - 1.5/kubernetes
   - 1.5/kubernetes/typed/apps/v1alpha1