[Feature] Image view

[Fix] Attendence upload, system not throwing an exception for wrong input.

[enhancement] added all permissions to permitted_documents_for_user

fix bug for "duplicate key name" when db init

Fixed issue in link field

Update bench-commands-cheatsheet.md

During the first init process for creating tables, if one field marked True for both "unique" and "search_index" , table creation will be failed. 

for example :

create table `tabItem Barcode` (
            name varchar(140) not null primary key,
            creation datetime(6),
            modified datetime(6),
            modified_by varchar(140),
            owner varchar(140),
            docstatus int(1) not null default '0',
            parent varchar(140),
            parentfield varchar(140),
            parenttype varchar(140),
            idx int(8) not null default '0',
            `item_barcode` varchar(140) unique,
`sku_id` varchar(140),
`unit_qty` varchar(140),
`_comments` text,
`_assign` text,
`_liked_by` text,
`store` varchar(140),
`retail_price` varchar(140),
`_user_tags` text,
`uom` varchar(140),
index `item_barcode`(`item_barcode`),
index parent(parent))
            ENGINE=InnoDB
            ROW_FORMAT=COMPRESSED
            CHARACTER SET=utf8mb4
            COLLATE=utf8mb4_unicode_ci

Backup and restore commands added

[minor-fix] replaced frm.call with frappe.call