lib.save function

[dgraziotin]

A library function to help to save a package on disk is required. Something like:

package = dpm.lib.init('/home/dgraziotin/Desktop/datapkg','test')
package.author = 'Daniel'
#update at '/home/dgraziotin/Desktop/datapkg/test'
package = dpm.lib.save(package)
package.author = 'Rufus'
#update package at '/home/dgraziotin/Desktop/datapkg/test2'
package = dpm.lib.save(package, '/home/dgraziotin/Desktop/datapkg/test2')
#package.name == 'test2' at this point?

The function should a wrapper around package.dist.write(path). From what I see, I will probably need to change the end of jsondist.py as follows:

if not os.path.exists(datadir):
   os.makedirs(datadir)

Many, MANY tests must be provided :)