Refactor the SecurityC::login() method to support also HTTP GET logins.

Modify the api.php to use the SecurityC::login() method to login.

It is now possible to request, for example, file data like this:

http://chris2/daniel/api.php?&username=chris&password=chris&action=get&what=file&parameters=chris/tractography/2013_01_18T19_29_43.178Z-1934/4578643_DTI-log/tract_meta-stage-2-dcm2trk.bash/final-trackvis/4578643_DTI.trkModify the api.php to use the SecurityC::login() method to login.

This enables access through Slice:Drop to internal chris data:

http://slicedrop.com/?http://chris2/daniel/api.php?&username=chris&password=chris&action=get&what=file&parameters=chris/tractography/2013_01_18T19_29_43.178Z-1934/4578643_DTI-log/tract_meta-stage-2-dcm2trk.bash/final-trackvis/4578643_DTI.trk