refactor: organized scripts (fossasia#1491)

Author: CloudyPadmal

.travis.yml

@@ -29,5 +29,5 @@ script:
 
 after_success:
   - bash scripts/prep-key.sh
-  - 'if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then bash upload-apk.sh; fi'
+  - 'if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then bash scripts/upload-apk.sh; fi'