Support password encryption using MD5 hex digest
Add country code from coolsms HTTP API document

Checked from PDF attachment
http://open.coolsms.co.kr/download/222303
Add country hash by country number
Adjust country code and destination number
Merge branch 'feature/adjust-contry-code' into develop
Coolsms does not support Canada (CA) directly

http://open.coolsms.co.kr/forum_qna/322057
Fix to support one digit country number like US
Fix invalid coolsms country number for JP
Fix invalid country number routing
Support reserve sms using epoch

coolsms only uses Asia/Seoul datetime for reserve sms.
So we use epoch to prevent confusion
Update change log
Update document
Bump up version
Merge branch 'release/0.002' into develop