CSCvh06508 - ECE should allow the user to set the Timezone or should take the system timezone

[Anthony97]

This issue also occurs in ECE 12.5. 

If I use ECE API to collect payload transcript activity data, the transcript is in UTC format and I have trouble to convert the timezone with current timezone. ECE API should have same timezone with server timezone or can be changeable since in ECE dashboard agent, the timezone can be changed.