Initial commit
Fixed namespace bug in aaigrid_driver
Gave aaigrid_driver lowercase names, keeping old camel case names as aliases.
reorganization into vector and raster submodules; renamed Grid to AAIGrid and added pointer for backwards compatibility

--HG--
rename : aaigrid_driver.py => raster/aaigrid_driver.py
rename : guppy_tests.py => tests/guppy_tests.py
rename : guppy.py => vector/guppy.py
rename : shapefile.py => vector/shapefile.py
Added gpxparser.py
Changed nomenclature in gpxparser.py to conform to standards.
Began adding projection and filtering methods to gpxparser.py
changed GPXParser method name from list() to getnames()
fixed namespace bug in aaigrid_driver.py
added max_dimension method to Multipoint
experimental stats module added to vector package with (slow) variogram estimator
added starter README file
clean-up in aaigrid_driver
Added max and min methods to aaigrid_driver.AAIGrid
performance improvements to AAIGrid tofile method
AAIGrid.get_profile now operates along segments lines
AAIGrid.tofile can now take either a filename or a file object
changed type-handling in AAIGrid.__init__
fixed Writer.record bug in shapefile.py
reverted last fix and added list contingency instead