This is a log of changes to the database schema.  Unfortunately I should have started this a long time ago
but didn't, so I'm trying to reconstruct the stuff prior to 4/2014.

5/27/2014:
	- add table application_preferences (like user_preferences), to server as optional
	properties for applications.  Planned use is to override global usage limit
	settings on a per app basis, same as they can be overriden on a per user basis via
	user_preferences

	As of today, only ngbwalpha has 5/1 and 5/27 changes.  cipres_copy(test) and cipres (prod)
	don't.  I'll write a script, may_2014.sql to make (and maybe reverse) the changes.

5/1/2014: Don't want users to have to create separate account for each CRA enabled app they use
so we need to keep track of which app submitted the job in tasks and job_stats.  
	- removed users.appname, removed EMAIL index and recreated it as unique index email (email,role)
	- added appname to job_stats and tasks
	- added job_stats.su_override column (can use when time is creditted back to us)


???:  new way of storing source docs, hashing content, not storing multiple copies of same content
	- Paul modified source_documents, adding signature field and index.  Use sdkrun org.ngbw.sdk.utils.MigrageDbFiles
	to handle the conversion.  It modifies the schema, then starts converting the data.  Let it finish 
	modifying the schema before starting cipres, but it can convert the data while cipres is running.

??? :  
	- alter table job_stats add  SU_PREDICTED bigint(20) ;
    - alter table job_stats add  SU_COMPUTED bigint(20) ;
    - alter table job_stats add  SU_CHARGED bigint(20) ;

Jan/2014 : I made the changes indicated in the convert*.sql scripts by running them.