Replace `listing()` methods with consistent solution

[Art4]

The listing() methods returns an array as name => id or id => name. These methods are inconsistent implemented and are based on a cache filled up by a previous call of list() what can be confusing.

We have to find a consistent solution for this problem.

Todo

• CustomField::listNames() Add CustomField::listNames() method as replacement for CustomField::listing() #408
• Group::listNames() Add Group::listNames() method as replacement for Group::listing() #398
• IssueCategory::listNamesByProject() Add IssueCategory::listNamesByProject() method as replacement for IssueCategory::listing() #406
• IssueStatus::listNames() Add IssueStatus::listNames() method as replacement for IssueStatus::listing() #409
• Project::listNames() Add Project::listNames() method as replacement for Project::listing() #411
• Role::listNames() Add Role::listNames() method as replacement for Role::listing() #412
• TimeEntryActivity::listNames() Add TimeEntryActivity::listNames() method as replacement for TimeEntryActivity::listing() #414
• Tracker::listNames() Add Tracker::listNames() method as replacement for Tracker::listing() #416
• User::listLogins() Add User::listLogins() method as replacement for User::listing() #419
• Version::listNamesByProject() Add Version::listNamesByProject() method as replacement for Version::listing() #421

[Art4]

Proposal

I've looked into every Api class and would like to propose replacing all listing() methods with methods like listNames(): array, listNamesByProject(): array and listLogins(): array. The response should be always an array with the int ids as keys and the names as value. This methods will be the base for a future replacement or drop of the getIdByName() methods. The nomenclature will allow us to add further methods such as Project::listIdentifiers() or User::listEmails() in the future.

The $reverse argument was introduced because of name collisions and can be dropped. The result will always have the int IDs as array key, so collisions should be avoided.

The $params argument to filter the entries will no longer supported. Instead all entries should be loaded by using multiple requests with 'limit' => 100 if necessary. The result will be cached in the api class in a special property, separated from the properties using by the all() methods.

The $forceUpdate argument can be dropped as well, because "deleting the cache" could be realized by dropping and reinstantiate the api class.

All in all, it looks like this:

mid-level API	listing() arguments	listing() returns	replacement
Attachment	-	-	-
CustomField	$forceUpdate, $params	['name' => id]	listNames(): [id => 'name']
Group	$forceUpdate	['name' => id]	listNames(): [id => 'name']
Issue	-	-	-
IssueCategory	$projectIdentifier, $forceUpdate	['name' => id]	listNamesByProject($projectIdentifier): [id => 'name']
IssuePriority	-	-	-
IssueRelation	-	-	-
IssueStatus	$forceUpdate	['name' => id]	listNames(): [id => 'name']
Membership	-	-	-
News	-	-	-
Project	$forceUpdate, $reverse, $params	[id => 'name'], ['name' => id]	listNames(): [id => 'name']
Query	-	-	-
Role	$forceUpdate	['name' => id]	listNames(): [id => 'name']
Search	-	-	-
TimeEntry	-	-	-
TimeEntryActivity	$forceUpdate	['name' => id]	listNames(): [id => 'name']
Tracker	$forceUpdate	['name' => id]	listNames(): [id => 'name']
User	$forceUpdate, $params	['login' => id]	listLogins(): [id => 'login']
Version	$projectIdentifier, $forceUpdate, $reverse, $params	[id => 'name'], ['name' => id]	listNamesByProject($projectIdentifier): [id => 'name']
Wiki	-	-	-