Time column should be labelled "date" in reports

[bewst]

At least under my 0.11dev trac installation, fields labelled "time" end up looking like a time of day when, surely, the date of entry is what you want to show in those reports. Changing "time as time" to "time as date" will fix that problem.

[Russ Tyndall]

(In [2785]) closes #1995

updated reports to use datetime as the column name instead of time.

refactored the reportsmanager a bit more and used these changes to make it update reports when their version changes as opposed to having to change my system version as well.

T&E (trac11) version 0.5.3