Hudge description in SO, PO, Q, I module ~"discussion"

If the Clients need write hudge description in SO, PO, Q, I module, there are limited on vtiger_inventoryproductrel.comment field, because it's a VARCHAR.

This SQL can fix this isseu: ALTER TABLE vtiger_inventoryproductrel CHANGE comment comment TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL