Provider scroll in Calendar's agenda views

[apooravc]

Continuing #1203, initial commit adds a horizontal scroll bar for provider scroll in agenda views of Calendar. It works by making Calendar slot table overflow its container. One issue was disappearance of scroll bar because of height of .fc-scroller and had to add a function to make sure it's visible in all possible states.

@teryhill Please have a look.

[teryhill]

The only issue I see is when there is no scroll needed we lost screen area.
before

After

[apooravc]

@teryhill did the calendar shrink in size/width in after image? Was the scroll bar not visible in before image? Both of these images are taken after applying this PR's changes, right? Or like one before and one after applying changes?

[teryhill]

The before image is before the pr was applied. the after is after it was applied. They are both the same screen size. Yes the calendar shrank after the pr was applied.

[apooravc]

@teryhill I think we should also test this with a large no. of providers to see if they are (Provider names) still getting crowded even after adding the scroll. About the shrinking, I tested on a new branch and it was working fine. I was able to shrink it by changing width to 600px in style block below:
.fc-agenda-view > table { width: 1200px; /* was fine with this value as in PR */ }

Could you check in inspect element tab if its value is 1200px or something else when shrinking is there? This one:

[teryhill]

@apooravc

[aethelwulffe]

I tested one branch today so far, and I will do the "tons o' providers" visual and function later today.

[apooravc]

@teryhill @aethelwulffe Latest commit adds a function to prevent crowding of columns based on number of providers in agenda views of Calendar. Also, Calendar is not shrinking on my machine and horizontal scroll is working fine. Please check if it's not.

[aethelwulffe]

WHY I THINK I WILL TEST THIS! WooHoo!

Note: I don't have any instances where an overflow is NOT needed. If it isn't needed, then you have space for a scroll bar anyway. It is a pretty narrow scroll bar, and as a compromise vs. having everything look like total poo, I am really good with that.

I need to set up for this I suppose, so I will run it in the morning with some real converted data.

[apooravc]

@aethelwulffe Tested this with a 1000 providers, display was fine in agenda views.

[aethelwulffe]

Outstanding. On my list for today now that I am going to be able to suck up the pain long enough to get something done. 1000 providers sounds awesome!

[aethelwulffe]

Current test looks good...at least within this branch. Other issues with calendar can be addressed. No other reviews, so I am doing this on my own volition. If we need to revert, fine, but we need to move to version 2.3 soon.