[Vimoutliner] small vo_checkbox patch

[Scott Scriven]

Hello.  This is a small patch to vo_checkbox.vim.  It makes VO's 
checkbox functions ignore lines which don't contain [X] or [_].

I find this useful because I tend to use more markers than those  
two and I don't want it to change those lines.  Every time I 
re-calculated task completion, these items were getting reset, so 
I just made VO ignore them.

Some of the non-standard markers I have found useful are:

  [F] failed
  [S] skipped
  [Z] snoozed (more on this later)
  [?] unsure

Additionally, I append an arrow to signify that an item is 
active.  This either means it's important, or that I'm currently 
working on it.

  [_] active <--

In case the patch gets mis-formatted, it's also online here:

  http://toykeeper.net/tmp/vim/vo_checkbox.only_X.diff

--- vo_checkbox.vim     (revision 1071)
+++ vo_checkbox.vim     (working copy)
@@ -258,6 +258,10 @@
        let l:done = 0
        let l:count = 0
        let l:i = 1
+       " ignore lines without [_] or [X] in them
+       if match(getline(a:line),"\\[[_X]\\]") == -1
+               return -1
+       endif
        while Ind(a:line) < Ind(a:line+l:i)
                if (Ind(a:line)+1) == (Ind(a:line+l:i))
                        let l:childdoneness = NewHMD(a:line+l:i)
@@ -286,7 +290,7 @@
    endif
    call setline(a:line,substitute(getline(a:line)," [0-9]*%"," ".l:proportion."%",""))
    if l:proportion == 100
-      call setline(a:line,substitute(getline(a:line),"\\[.\\]","[X]",""))
+      call setline(a:line,substitute(getline(a:line),"\\[_\\]","[X]",""))
       return 100
    elseif l:proportion == 0 && l:count == 0
       if match(getline(a:line),"\\[X\\]") != -1
@@ -297,7 +301,7 @@
              return -1
       endif
    else
-      call setline(a:line,substitute(getline(a:line),"\\[.\\]","[_]",""))
+      call setline(a:line,substitute(getline(a:line),"\\[X\\]","[_]",""))
       return l:proportion
    endif
 endf



-- Scott