[$60] Fix up the Gantt charts

[jmgasper]

@suppermancool - We need to fix up the Gantt charts a bit:

Issue 1

The chart on the new challenge page is rendering differently than the edit challenge page. Ideally, these would be the same:

New challenge

Edit challenge

Issue 2

In terms of the phase duration, I got this clarification, so we can got with this assumption:

go now with the assumption that phase duration is hours

[jmgasper]

Contest https://www.topcoder.com/challenges/30123335 has been created for this ticket.

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[jmgasper]

Contest https://www.topcoder.com/challenges/30123335 has been updated - it has been assigned to diazz.

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[suppermancool]

@jmgasper in the existing code if the backend return missing data or when create new challenge the frontend will calculate the challenge timelines locally.
For this i will:

• Hide the timeline if the backend return broken phase.
• In create new challenge i will hide the timeline until getting the response of first request of creating new draft challenge.

is this ok?

[jmgasper]

Yep, that sounds good, thanks

[suppermancool]

@jmgasper done in #180. i removed all local calculation for timeline, the timeline should come from backend now