Merge pull request #9 from KnowSheet/review

File storage queue
[android] Fixed invalid if in device id retrieval.
[android] Added READ_PHONE_STATE permission for demo purposes.
[android] Removed unnecessary debug mode activation.
Code review fixes
[android] Fixed crash caused by invalid initialisation order.
[android] Forced statistics uploading on WiFi connected event
Append installation id event for each sent packet.
[android] Gzip data passed to the server on the http transport level.