Add ChangeLog.txt
Add ChangeLog.txt

dropbox/dropbox-sdk-php,demisang/dropbox-sdk-php,dropbox/dropbox-sdk-php,itsazzad/dropbox-sdk-php,sayfulit/dropbox-sdk-php,itsazzad/dropbox-sdk-php,TimeDoctorLLC/dropbox-sdk-php,demisang/dropbox-sdk-php,TimeDoctorLLC/dropbox-sdk-php,sayfulit/dropbox-sdk-php