kohabug 2417 Removing hardcoded query limit from reports

kohabug 2417 Removing hardcoded query limit from reports

This patch removes a hardcoded 'LIMIT 20' which was added to all report queries
thus limiting all reports to only the first twenty rows of applicable data. In
its place this patch introduces code to paginate through all applicable data,
regardless of how many rows are available. The code will also honor any user
defined 'LIMIT' in reports based on SQL entered directly by the user.

This patch also adds column labels to 'tab' and 'csv' files generated by reports.
NOTE: Only user defined 'LIMIT's apply to 'tab,' 'csv,' and 'text' files.

Signed-off-by: Galen Charlton <galen.charlton@liblime.com>
Signed-off-by: Joshua Ferraro <jmf@liblime.com>