Revision 424308

MFH: r424292

- Add GCC option, turned on by default, to force compilation using
  GCC, this fixes a problem in zathura which shows up only when girara
  is compiled wth clang [1]
- Make the port use gnu99 C standard to allow it to compile with
  the default gcc 4.8
- Remove USES=compiler since it's not needed anymore
- Small cosmetic change to the REINPLACE_CMD lines
- While here, make the build verbose

PR:		213595
Submitted by:	Michael Danilov <mike.d.ft402@gmail.com>

Approved by:	ports-secteam (feld)