Transform gpx2spatialite into a proper python package

Move extra scripts to bin folder and sql files to data folder withn the
package folder. Chnage to rst README. Add GPL license file.
Check for different spatialite libraries
Use string.format instead of %
Fix create_db.sql script path in unit test
Fix an output message
Change load_extension name to libspatialite.so
Use new print function with parentheses
Use dot when importing spatialite_finder
Remove test database if older than 1 day
Do not use spatialite tool to create database
Add todo entry
Move create_new_db code to separate function
Move some helper functions to db_helper.py
Add dot for intra-package import
Fix version compare
Move print statement to right place
Use distutils LooseVersion for version compare
Add __version__ attribute
Move code from lib to script
Update README