document download report (result can be export to excel)

[wangmj]

search by date range、users
=============result like this=====================
from 2010-10-01 to 2010-10-07

user num
okmAdmin 24
test0 34
test1 51
... ...

[jllort]

reports are based in jasper reports, that means can be converted to pdf, rtf, csv, etc... csv is file that can be imported int spreadsheet.

Could be interesting indicating the format to exporting, I think it's not very complicate doing. I'll add into roadmap.