dsl helpers to be documented

[ehsandeep]

Description

The following dsl functions have either missing documentation or the existing one needs to be updated:

• [ ] sort
• [ ] uniq
• [ ] sha512
• [ ] contains_all
• [ ] contains_any
• [ ] rand_ip
• [ ] to_unix_time
• [ ] to_number
• [ ] to_string
• [ ] dec_to_hex
• [ ] hex_to_dec
• [ ] oct_to_dec
• [ ] bin_to_dec
• [ ] substr
• [ ] aes_cbc
• [ ] date_format (remove)