fix: Abstract input log folder to parameters

issue: https://github.com/Telenav/osrm-backend/issues/65

docker-orchestration/elk-compose/docker-elk/.env

@@ -1 +1,2 @@
 ELK_VERSION=7.3.1
+DATA_PATH=/Users/xunliu/Desktop/go/src/github.com/Telenav/logs/

docker-orchestration/elk-compose/docker-elk/README.md

@@ -1,10 +1,9 @@
 # ELK Stack
 
-Specify your log location in docker-compose.yml->logstash->volume mapping
+Specify your log location in .env file and change DATA_PATH there
 ```
 // change "/Users/xunliu/Desktop/git/elastic-example/data/" to your data location
-// later will abstract this to parameters
-/Users/xunliu/Desktop/git/elastic-example/data/:/data
+DATA_PATH=/Users/xunliu/Desktop/go/src/github.com/Telenav/logs/
 ```
 
 Start
@@ -20,6 +19,8 @@ docker-compose -f docker-compose.yml down -v
 You could go to following link for Kibana
 ```
 http://localhost:5601
+// username: elastic
+// password: changeme
 ```
 
 If you need one component specific logs, you could use

docker-orchestration/elk-compose/docker-elk/docker-compose.yml

@@ -28,8 +28,9 @@ services:
       context: logstash/
       args:
         ELK_VERSION: $ELK_VERSION
+        DATA_PATH: $DATA_PATH
     volumes:
-      - /Users/xunliu/Desktop/git/elastic-example/data/:/data/
+      - ${DATA_PATH}:/data/
       - type: bind
         source: ./logstash/config/logstash.yml
         target: /usr/share/logstash/config/logstash.yml