[Gpsbabel-misc] Building gpsbabel-1.5.4 with Qt4

[lj <lj...@po...>]

I realize Qt4 is no longer supported, and Qt-5.2 or higher is required. But my 
Linux distribution (Slackware-14.2) has Qt-4.8.7, and I'm not about to try to 
upgrade Qt on my own. So I made a few changes and built gpsbabel-1.5.4 with 
Qt4. If anyone else is stuck on Qt4 and wants to build the latest gpsbabel, 
here is a summary of what I did. (I have a patch file I can post if there is 
any interest.)

   Makefile.in : delete geojson.o from the list of ALL_FMTS

   main.cc : remove the check for QT_VERSION >= 5.2.8 (or change it to 4.8.0)

   vecs.cc : remove the declaration and block for geojson format

Then just the usual configure; make. Everything seems to work, although you 
lose the new (undocumented?) geojson format.