Added multi-element support for OS & Monitor

Users can select one or more elements for all pre-existing OS metrics &
any non-ranged retained service monitor metrics.
Fixed text being cut off in the select box
Added network device & ranged data support

User can now graph network device by selecting the metric, element and
port(s).  User can also graph ranged data by selecting metric,
element(s) and range object(s).
deleted the example folders under bootstrap & highcharts
should shrink the size of the upk by 1MB
added if (isset($_GET[''])) blocks around all the incoming variables to prevent php warnings
Added scroll bar and minor UI changes to work better in small gadget panels.
Merge branch 'master' of lab-toolbox.css.local:plugins/uptime-metric-chart
Merge branch 'master' of lab-toolbox.css.local:plugins/uptime-metric-chart
built version 2.5 of the upk that includes all the new JS & PHP
initial changes to get_metrics.php to support Oracle & Mysql for all the new graph types
Expanded Details in the getmetrics.php & readme.txt on how to setup the required Oracle ODBC Drivers on both Windows & Linux monitoring stations.
added kevin's updates to the readme.txt for Oracle ODBC Driver install steps
committed the latest version of the 2.5 upk with updated readme.txt
Merge branch 'master' of https://github.com/uptimesoftware/uptime-metric-chart
updated readme.md with details for version 2.5 & upgrade instructions.
fixed link to readme.txt in readme.md
Update README.md

fixed the relative link to readme.txt
Update readme.txt

updated version number & added details for upgrading from an earlier version of the gadget.