Bump version to 0.89
[Download] Fix and complete Download API

Refactored Filesytem and Download API to share code
related to virtual roots.
Pass TCT tests.
Fix example.

BUG=XWALK-1070
Merge pull request #352 from eurogiciel-oss/XWALK-1070

[Download] Fix and complete Download API
Bump version to 0.90
[Tizen][SSO] Fix for GetIdentity

All inputs are validated to avoid blank input from user.

BUG=XWALK-2268
Merge pull request #364 from izaman/master

[Tizen][SSO] Fix for GetIdentity
zones, subscribe and unsubscribe support