windeployqt: Compile on UNIX.

Rearrange code within OS-ifdefs.
Change runProcess to take a binary and a list of arguments
since that fits better with execvp.

Change-Id: Ib6733c615e6dfc6b483e457ff90a59a1c0dcaded
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
windeployqt: Fix location of web process.

Change-Id: I3b926f189a48aa391e3c3e4aa1edea518d5cf13e
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
windeployqt: Handle simple symbolic links in updateFile().

Preparing the deployment of shared libraries and their version
links on Unix.

Change-Id: Iee9e25e5364209c0a4aafbd6d10c18e64113c971
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>