Make PGN parser immune to unprotected time stamps

The parser choked on time stamps of the form dd:dd or dd:dd:dd if one
of the fields happened to be 00, because it wouldmistake that for a
non-compliant king-side castling. By excluding this interpretation when
the 00 is immediately preceded or followed by ':' this is now prevented.
Fix book creation

Due to duplicate use of the same file pointer variable the game file would be
closed before any games were read from it.
Fix GUI book after setup position

The routine to send move to the engine would automatically append a 'go'
is a preious setboard had put the engine in force mode, but this should
not happen on a book hit, where the engine should even be put in force mode
if it was not yet there.
Allow drops / promotions/ deferrals to be edited into book

For no real reason only NormalMove would be accepted when parsing the list
of book moves.
Allow entry of negative numbers in spin control (WB)

Windows numeric controls do not accept negative numbers, so in case the
range of a spin option can go negative, the style ES_NUMBER should not be
set on the control.
Fix grabbing of selected piece

A second static click on a selected piece should deselect it, but an attempt
to drag an already selected piece should not 'bounce off'. It was already
possible to move a selected piece to another square, but the dragging was
not animated. This is now fixed, by only skipping the code to start dragging
when the second click is part of the only-move double-click for only capture.
(Before it was skipped on any second click.)
Fix initial board sizing WB

The initial board size was based on the assumption the board would be 8x8.
This could push auxiliary windows off screen if the board was smaller,
after which EnsureOnScreen would undock them and park them in the upper-
right corner before the board assumed its true size. InitPos() is now called
before the initial sizing to et the board format correctly, InitDrawingSizes()
had to be made resitant to calling before a board size was picked for this
(because InitPos() might call that too).
  ActivateTheme() now uses the new board size, not the previous one (as was
indicated by size -2), so that -boardSize specifications inside a theme
will take effect.
  Board size petite should not be forbidden for Shogi; all pieces exist there.
Fix -zippyVariants option

Due to the change of cps->variants from (char []) to (char *), copying
zippyVariants to it on behalf of v1 engines would no longer work. This
is fixed by using ASSIGN() in stead of safeStrCpy().
updated Changelog, NEWS, etc.
new version number for release 4.7.2
updated po files for new release (make distcheck)