Tasknote [N] should not count first line or blank lines

[linuxcaffe]

The [N] of items below the fold is an excellent thing, and could be somewhat misleading.

When the line says

== Task details == [9]

I actually have 7 attributes listed, and under

== Annotations == [2]

there are no annotations. (same for == Notes == [2])

Now I understand this is a line count, and subtracting "2" will usually give the actual number of items below, but it may be worth considering excluding the heading and any blank lines from that count, for details, Annotations and Notes.

An exception to this might be the very first heading of the task, with the description, as that contains several sections, and overall number-of-lines, including other headings and blank lines, makes as much sense here as anything else.

[linuxcaffe]

should "tasknote" filetype be defined in ../ftdetect/task.vim ?