Add ability to choose cohort name

[GuybrushTreepwood]

The cohort name is the group name (CN).
In our directory, group names are not user friendly.
I changed a little bit the code to use the DisplayName attribute of the group to name the cohort.

We need a new setting to choose which attribute to use to name the cohort.

[mackensen]

This is a good idea and shouldn't be too hard to implement.

[GuybrushTreepwood]

as I wrote here,

here's how I managed the change in code to use the DisplayName (if set) of a group instead of the CN:

In locallib.php.

In function ldap_get_grouplist

line 148:
$ldapresult = ldap_search($ldapconnection, $context, $filter, array ($this->config->group_attribute));

becomes
$ldapresult = ldap_search($ldapconnection, $context, $filter, array ($this->config->group_attribute, "displayName"));

line 151:

$ldapresult = ldap_list($ldapconnection, $context, $filter, array ($this->config->group_attribute));

becomes

$ldapresult = ldap_list($ldapconnection, $context, $filter, array ($this->config->group_attribute, "displayName"));

line 162:

array_push($fresult, ($groups[$i][$this->config->group_attribute][0]));

becomes

array_push($fresult, ($groups[$i]));

in function sync_cohorts_by_group

replace line 639:

foreach ($ldapgroups as $groupname) {

with

foreach ($ldapgroups as $ldapgroup) {
$groupname = $ldapgroup[$this->config->group_attribute][0];
if($ldapgroup["displayname"][0]===NULL){
$displayName = $groupname;
}
else{
$displayName = $ldapgroup["displayname"][0];
}

could be improved with the use of a variable for the displayname of the cohort...