Added trial settings to synchronize trials based in the whmcs product settings.
Added year and client id limits in the addon settings.
Redesigned product and customer export area to be able to filter the selection.
Fixed issue with html code rendered incorrectly in error logs.
Added client email check in the chartmogul client external id to avoid duplicated entries.
Fixed issue with new invoices paid not exported when the client was still not exported.
Added beta product upgrade support. Whmcs does not keep track of old product ids when they are upgraded creating issues with the chartmogul product upgrade descriptions when exported, new orders will be tracked by the addon and will be displayed correctly as upgrades in chartmogul
