Fixed extents of image warping.
io init
Merge pull request #20 from bblay/ioinit

Made the io module work.
Refinement changes to image transformations.
Some example improvements.
Merge pull request #24 from pelson/img_extent_fix

Image transformation extent fixes. Documentation enhancements.
Tiled image support. An external API is still needed.
Further tidy up of the img tile interface.
Merge pull request #29 from pelson/img_tiles

Tiled image support. An external API is still needed.
rotated geodetic
Add ability to check for copyright/licence header, and fix missing headers.
Merge pull request #34 from rhattersley/header_check

Copyright/licence header checks
Pickle support for a CRS
Minor example changes.
Merge pull request #38 from pelson/small_example_changes

Minor example changes.
Rudimentary support for IGH
Merge pull request #37 from pelson/picklable_crs

Pickle support for a CRS
Added default ellipse to CRS to prevent error on systems without proj_def.dat.
Merge pull request #39 from rhattersley/igh

Rudimentary support for IGH
Added the image nest class. Tests needed.