fix: make skipfold actually move the cursor #276

commit e914b73 changed the line 
    call cursor(foldend + 1, 1)
to
    call line(foldedge)
    call col(a:reverse ? 1 : '$')

This is obviously nonsense - in the end, skipfold() never actually moves the
cursor when it says so. The reason no one has caught this so far is that
wherever we use the function, we _continue_ the search loops in this case (on
return value `1`), go on finding the next match, so if the fold is contained by
the window area, we will eventually reach a target outside the fold anyway, if
there is one (by doing some unnecessary work).

fix #274

autoload/sneak/util.vim

@@ -71,7 +71,7 @@ func! sneak#util#wincol1() abort
   return c
 endf
 
-"Moves the cursor to the first line after the current folded lines.
+"Moves the cursor to the outmost position in the current folded area.
 "Returns:
 "     1  if the cursor was moved
 "     0  if the cursor is not in a fold
@@ -83,8 +83,8 @@ func! sneak#util#skipfold(current_line, reverse) abort
                 \ || foldedge >= line("w$")  "fold ends at/below bottom of window.
       return -1
     endif
-    call line(foldedge)
-    call col(a:reverse ? 1 : '$')
+    call cursor(foldedge, 0)
+    call cursor(0, a:reverse ? 1 : col('$'))
     return 1
   endif
   return 0