Update the dea to use the new logger

Test plan:

- Ran BVTs locally
- Deployed to my bosh instance, ran BVTs against it

Change-Id: I143a7a3f6138520a9a7286c90cf10253bdf5ddd2

Gemfile

@@ -12,6 +12,7 @@ gem 'yajl-ruby', :require => ['yajl', 'yajl/json_gem']
 gem 'logging', '>= 1.5.0'
 
 gem 'vcap_common', :path => '../common'
+gem 'vcap_logging', :require => ['vcap/logging']
 
 group :test do
   gem "rspec"

Gemfile.lock

@@ -49,6 +49,7 @@ GEM
       daemons (>= 1.0.9)
       eventmachine (>= 0.12.6)
       rack (>= 1.0.0)
+    vcap_logging (0.1.0)
     yajl-ruby (0.8.2)
 
 PLATFORMS
@@ -67,4 +68,5 @@ DEPENDENCIES
   rspec
   thin
   vcap_common!
+  vcap_logging
   yajl-ruby

config/dea.yml

@@ -5,7 +5,8 @@ filer_port: 12345
 mbus: nats://localhost:4222/
 intervals:
   heartbeat: 10
-log_level: DEBUG
+logging:
+  level: debug
 multi_tenant: true
 max_memory: 4096
 secure: false

config/dea2.yml

@@ -5,7 +5,8 @@ filer_port: 12346
 mbus: nats://localhost:4222/
 intervals:
   heartbeat: 10
-log_level: DEBUG
+logging:
+  level: debug
 multi_tenant: true
 max_memory: 4096
 secure: false

lib/dea/agent.rb

@@ -24,6 +24,7 @@
 
 require 'vcap/common'
 require 'vcap/component'
+require 'vcap/logging'
 
 module DEA
 
@@ -73,8 +74,8 @@ class Agent
     APPS_DUMP_INTERVAL = 30*60
 
     def initialize(config)
-      @logger = VCAP.create_logger('dea', :log_file => config['log_file'], :log_rotation_interval => config['log_rotation_interval'])
-      @logger.level = config['log_level']
+      VCAP::Logging.setup_from_config(config['logging'])
+      @logger = VCAP::Logging.logger('dea')
       @secure = config['secure']
       @enforce_ulimit = config['enforce_ulimit']
 
@@ -203,6 +204,7 @@ def run()
 
       NATS.on_error do |e|
         @logger.error("EXITING! NATS error: #{e}")
+        @logger.error(e)
         # Only snapshot app state if we had a chance to recover saved state. This prevents a connect error
         # that occurs before we can recover state from blowing existing data away.
         snapshot_app_state if @recovered_droplets
@@ -211,7 +213,7 @@ def run()
 
       EM.error_handler do |e|
         @logger.error "Eventmachine problem, #{e}"
-        @logger.error("#{e.backtrace.join("\n")}")
+        @logger.error(e)
       end
 
       NATS.start(:uri => @nats_uri) do