+ fix region reading, so png's can be used in raster.input
- added testcase for wkb format parser (still to be extended). complement of 4d85cd2c4300f5f79dd9bac2791aa5f8f05432e7
Merge branch 'master' of github.com:mapnik/mapnik
+ mapnik c++ naming style
+ make image_reader non-copyable
+ add png file guard
Merge remote-tracking branch 'origin/master'
avoid unused arguments compiler warning
avoid png_struct leak - refs #1783
further cleanup png struct handling - refs #1783
refactor jpeg reader to close fd after read - refs #1783
fix memory leak when reading invalid tiff - refs #1783
add missing test file
set TIFFSetErrorHandler to null to start to avoid tiff from printing to stderr on fail - refs #1783
remove ltdl to reduce dependencies and because calling dlopen/LoadLibrary is easy
Merge pull request #1804 from mapnik/drop-ltdl-dependency

remove ltdl
+ figure out raster format from file name unless explicitely specified by
 'format' parameter.
+ avoid  std::string->C-string->std::string round trip
mapnik-config: start reporting dependency link flags again as they are needed to link command line apps (though not for bundles)
use mapnik::noncopyable