Reorg multiple sections consolidate what you can/can't do to the schema into one section and move to the top of the Tracker Schema section.. Also outline how you *can* change the type of a property. In the "Classes and Properties - creating a new information store section", add new Method subsection after Properties subsection. Place all 4 method sections in there moving them from below. Move IssueClass section before FileClass section because IssueClass incorporates links to FileClass not the other way around. Fix indexes.

def init_severity(db, cl, nodeid, newvalues):
    """Make sure severity is set on new issues"""
    if 'severity' in newvalues and newvalues['severity']:
        return

    normal = db.severity.lookup('normal')
    newvalues['severity'] = normal

def init(db):
    db.issue.audit('create', init_severity)