Add config in tjqueue component for read count limit

[vijaykhollam]

Existing problem -
Currently, in com_tjqueue we have added as default count limit is 50 or we can pass it in the cron parameter.

Proposed Solution,

We have added config for default limit in the tqueue component in options tab and used it. Now, we can change the deafult limit through the config and don't need to do changes in the cron parameters.