Trial an update to Mono 3.10.0

[dsyme]

OK, yes, the main problem is the failure in Array.dropRange. The following coe makes 19 out of 20 errors go away:

  let inline dropRange first last (data:'T[]) =
    if last < first then invalidOp "The first index must be smaller than or equal to the last."
    if first < 0 || last >= data.Length then invalidArg "first" "The index must be within the array range."
    Array.append (if first = 0 then [| |] else data.[.. first - 1]) (if last = data.Length - 1 then [| |] else data.[last + 1 ..])

There is another error in testing the documentation creation which is an FSharp.Data not found error. I think this is much less serious and you could probably just disable that test on Mono since I think you build docs on Windows anyway.

[dsyme]

Closed in favour of this: https://github.com/BlueMountainCapital/Deedle/pull/282