pathtools: add a helper to synchronize all copies
pathtools: add a helper to synchronize all copies

The `mingw-w64-pathtools` directory does not contain a package
definition, on purpose: for ease of maintenance, we do not patch users
of this code to link to a library, but we patch in the source code
directly.

Which means that we have to maintain copies of this code, and after
every update to `mingw-w64-pathtools/pathtools.[ch]`, we have to
synchronize those copies and increment pkgrels.

Let's add a simple shell script to do that job for us.

Signed-off-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>

Optiligence/MINGW-packages,oroppas/MINGW-packages,stahta01/MINGW-packages,oroppas/MINGW-packages,Chocobo1/MINGW-packages,jtanx/MINGW-packages,JPeterMugaas/MINGW-packages,Alexpux/MINGW-packages,oscarfv/MINGW-packages,Alexpux/MINGW-packages,InitialForce/MINGW-packages,Ede123/MINGW-packages,JPeterMugaas/MINGW-packages,JPeterMugaas/MINGW-packages,fabiangreffrath/MINGW-packages,InitialForce/MINGW-packages,fabiangreffrath/MINGW-packages,Chocobo1/MINGW-packages,oroppas/MINGW-packages,JPeterMugaas/MINGW-packages,stahta01/MINGW-packages,Ede123/MINGW-packages,jtanx/MINGW-packages,Optiligence/MINGW-packages,Alexpux/MINGW-packages,oroppas/MINGW-packages,Ede123/MINGW-packages,lhmouse/MINGW-packages,fabiangreffrath/MINGW-packages,stahta01/MINGW-packages,stahta01/MINGW-packages,stahta01/MINGW-packages,lhmouse/MINGW-packages,jtanx/MINGW-packages,fabiangreffrath/MINGW-packages,Optiligence/MINGW-packages,Ede123/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,InitialForce/MINGW-packages,JPeterMugaas/MINGW-packages,jtanx/MINGW-packages,fabiangreffrath/MINGW-packages,JPeterMugaas/MINGW-packages,oscarfv/MINGW-packages,lhmouse/MINGW-packages,stahta01/MINGW-packages,oscarfv/MINGW-packages,Alexpux/MINGW-packages,lhmouse/MINGW-packages,Alexpux/MINGW-packages,Alexpux/MINGW-packages,oroppas/MINGW-packages,Optiligence/MINGW-packages,Chocobo1/MINGW-packages,oroppas/MINGW-packages,oscarfv/MINGW-packages,fabiangreffrath/MINGW-packages