update test description
Simplify code with enum
An Add-on must be identified only by its ID and VERSION. distribution  and appServer types are constraints on which we must filter entries. Use Enums lists for supported distributions an appsrv
Add test for AM_CAT_07 :  At merge, de-duplication of add-on entries of the local and remote catalogs is done using  ID, Version, Distributions, Application Servers as the identifier. In case of duplication, the remote entry takes precedence
Display only entries compatible with the local PLF application server and distribution types
Use always remoteCatalog instead of centralCatalog
 AUTOUPD_01 : Don't return the catalog entry used for the add-ons manager auto-update. It's not an add-on
AM-9
* AM_CAT_08 : Add controls on JSON parsing
* AM_CAT_09 : Catalog entries that are malformed or duplicate will be silently ignored unless the --verbose switch is used. In which case a warning will be logged.
-f for --force and -s for --snapshots aren't in specs
AM-24, AM-55, AM-56, AM-57, AM-58 : Allows to list and install unstable versions of add-ons