The problem was that a window wouldn't resize while prompting the user
for input. These changes allows the input methods in nnn to resize
properly if KEY_RESIZE is defined.

A more portable solution would be hooking the WINCH signal and update
the xlines value from there along with some resized flag.

In some cases the full window isn't redrawn until the user has finished
the input. This is because in some functions I wasn't sure the current
"path" was available.

2 changes:
- Toggle nav-as-you-type with left single/double click below last entry
- Handle mouse events when filter is on

Visit parent is now left single click outside context nums on top row.

This is limited to libncurses support of full mouse scrolling.
Ref: https://invisible-island.net/ncurses/man/curs_mouse.3x.html#h3-Mouse-events

incase the user just lost access, it would be better to remember the
selected directory to keep it highlighted.

The previous behaviour would exit nnn when the CWD disappeared.

This reverts commit afdfcecb9c.

These three lines are exact copy of 4555-4557.
As opener is not changed in between, we can delete these

Fixes warning on CentOS 6:

  src/nnn.c:754: warning: ignoring return value of 'fwrite', declared with attribute warn_unused_result

Building on i386 (NetBSD or Debian):

  src/nnn.c: In function 'selectiontofd':
  src/nnn.c:783:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    while (pos <= lastpos) {
               ^
  src/nnn.c:791:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (pos <= lastpos) {
             ^
  src/nnn.c: In function 'showcplist':
  src/nnn.c:823:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (pos && pos == copybufpos)
                   ^
  src/nnn.c: In function 'xlink':
  src/nnn.c:1955:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    while (pos < copybufpos) {

The new location is ~/.config/nnn/.lastd