As a user, I want to be able to set the maximum number of issues output by the gadgets

Currently, the Xray Cloud gadgets are limited to 1000 issues being output at a time, presenting a restriction that was not present on Server/DC, and limiting the usage of the gadgets in the Cloud environment.

As a user, I want to be able to set (or even remove) the limit of issues output by the Xray gadgets in my site.