Add LDAP support.

[Denney-tech]

Is your feature request related to a problem? Please describe.
Please add ldap support. The spec.ldap.config CRD from the old pulp resource type is completely ignored in the new operator. In theory, all of the requisite values can be added in pulp_settings:, but there's some problems with values being treated as strings instead of dictionaries or methods.

E.g.

spec:
  pulp_settings:
    auth_ldap_group_type: NestedActiveDirectoryGroupType()

Expected value:
AUTH_LDAP_GROUP_TYPE = NestedActiveDirectoryGroupType()

Actual value:
AUTH_LDAP_GROUP_TYPE = "NestedActiveDirectoryGroupType()"

Since this is being injected into settings.py, it's very important that this is not quoted and treated as string.

Describe the solution you'd like
I like the way ldap_password_secret: and extra_settings: work in AWX-Operator better than in the Pulp-Operator. I've had better luck with setting all the right values there.

Need documentation as well.

Describe alternatives you've considered
Pulp-operator "works" for me, but just barely.

Additional context
I just want Galaxy to play nicely with AD.

[Denney-tech]

#98 fixes AUTH_LDAP_GROUP_TYPE = NestedActiveDirectoryGroupType() specifically, but it would still be preferred to have an ldap secret to apply the ldap password to.

[josemgom]

Agree. It would be better if we have a way to define the password in a secret, that would open the door to use something like sealed secrets to store it in git repositories.