First steps to write ints instead of doubles for DB drivers.
Merge remote-tracking branch 'origin/master' into dbintwriter

Conflicts:
	plugins/sqlite/drivers/SQLiteCommon.hpp
Merge branch 'master' of https://github.com/PDAL/PDAL into issues-599
Replace stuff I shouldn't have removed.
Add support for writing int32's to DbWriter.  Schema mods still needed.
Remove XML schema reader/writer.
Remove exceptions from XML schema.
Remove pointer wrappers.
Remove storage of DimTypes (use XMLDims instead)
Ignore float equality warning.
Remove PDAL_HAVE_LIBXML2 from XMLSchema files.  Use build system
instead.
Remove XMLSchema from Info.hpp.
Make DbReader.  Hook to pgpointcloud.
Merge branch 'master' of https://github.com/PDAL/PDAL into issues-599

Conflicts:
	plugins/pgpointcloud/test/PgpointcloudWriterTest.cpp
Writer support for scaled 32-bit ints in OCI.
Merge branch 'master' of https://github.com/PDAL/PDAL into issues-599

Conflicts:
	plugins/oci/io/OciWriter.hpp
	plugins/pgpointcloud/io/PgWriter.cpp
	plugins/pgpointcloud/test/PgpointcloudWriterTest.cpp
	plugins/sqlite/io/SQLiteWriter.hpp
	src/CMakeLists.txt
	src/XMLSchema.cpp
Merge branch 'master' of https://github.com/PDAL/PDAL into issues-599

Conflicts:
	plugins/oci/test/OCITest.cpp
DbReader for OCI.
SQLite checked with compression and integrated into int I/O.
Write scale into XMLSchema.
Merge branch 'master' of https://github.com/PDAL/PDAL into issues-599
make the crop filter a builtin filter once again
_VARIADIC_MAX must be increased on msvc for gtest