Charbuf uses std::ios::pos_type, not Charbuf::pos_type #512
Merge pull request #514 from PDAL/issues/514-charbuf-export

Closes #514
Turn off NITF by default

Don't build NITF support by default. If NITF support is requested, error
if we can't find Nitro.
Merge pull request #582 from gadomski/nitf-default-off

Turn off NITF by default
Merge branch 'master' into issues/562-laz-perf