Lower the number of LDAP requests for most actions

That commit:

- Add "full", selfcontained version of configuration entities:
  - FullActiveTechnique, FullActiveTechniqueCategory
  - FullNodeGroupCategory, FullRuleTargetInfo
- Add method in repository to get them efficiently:
  - RoLDAPDirectiveRepository#getFullDirectiveLibrary
  - RoLDAPNodeGroupRepository#getFullGroupLibrary
- Add a service to build an HTML tree from:
  - DisplayDirectiveTree
  - DisplayNodeGroupTree
  - and use them in node details, rules/directive/group edit form
- Make immutable some data structures:
  - RuleVal
  - NodeConfiguration (and make it a real sealed data tree)
  - Values of directives (when used in policy draft)
- remove a BUNCH of I/O intensive service method and make more
  efficient used of them (Deployment service, etc)
- Simplify RuleEditForm:
  - used tree displaying service
  - make and use a RuleApplicationStatusService
- clean some warning and typos (tuples missings () in Some(), etc)
- type some string (nodeIds, etc)