deleteMarkedTimespan requires too specific of a call

deleteMarkedTimespan requires a very specific configuration to delete a marked timespan. For example, if I place a timespan with the start and end date, I need to know the old start and end date in order to delete the timespan on that one single timeline. Instead, if I just pass the sections: {timeline: id} as the config, I would argue that the default behavior should be to delete the markedTimespan on that timeline. Either way, for my purpose, I called

        sections: { timeline: }

and added

if(typeof a[h][f] != 'undefined' && typeof d == 'undefined' && e == "default"){
       delete a[h][f];

into scheduler._delete_marked_timespan_by_config located in dhtmlxscheduler_limit.js

I looked for a fix for a while, before I just hacked around it.

Just thought someone might benefit from my solution. Just keep in mind this is only useful when you have one markedtimespan on a timeline. The timelines I have are limited use, and I want a way of notifying the user when the timeline is over so they can remove it from their community.

Yep, the deleting of timespan is far from perfect. We will look how to improve this functionality in next versions.