Support official LLDAP container out of the box

[languagegame]

It would be nice to make this script compatible out of the box with the official stable docker image for LLDAP, which is based on Alpine Linux. Alpine Linux uses busybox, which provides a subset of capabilities of the GNU text utilities. I tested this script in the LLDAP docker image, and nearly all of it works, which is great.

That said, this script depends on the column program, which unfortunately not included in the docker image or busybox. The column program is referenced in four places in this script:

• listUsers()
• listGroups()
• schemaListUserAttributes()
• schemaListGroupAttributes()

Those 4 occurrences each have the output of other command(s) piped to it like:
command(s) | column -ts $'\t'

This results in errors when running certain commands of lldap-cli in the official LLDAP container. For example, if I run the following command, I get these error messages:
lldap-cli user info admin
/bin/lldap-cli: line 163: column: command not found
/bin/lldap-cli: line 163: column: command not found

I also get similar errors when running these commands for similar reasons:
lldap-cli schema attribute user list
lldap-cli schema attribute group list

There is a manual work around, which is to open a console in the LLDAP container and install the util-linux package.
apk update
apk install util-linux

However, it would be nice to have this script work out of the box. Given only 4 occurrences of the column program, perhaps there is a way to remove the dependency upon it.