[enh] no cli option to avoid removing an application on installation failure

data/actionsmap/yunohost.yml

@@ -436,6 +436,9 @@ app:
                 -a:
                     full: --args
                     help: Serialized arguments for app script (i.e. "domain=domain.tld&path=/path")
+                -n:
+                  full: --no-remove-on-fail
+                    help: Debug option to avoid removing the app on a filed installation
 
         ### app_remove() TODO: Write help
         remove:

src/yunohost/app.py

@@ -440,7 +440,7 @@ def app_upgrade(auth, app=[], url=None, file=None):
     logger.success(m18n.n('upgrade_complete'))
 
 
-def app_install(auth, app, label=None, args=None):
+def app_install(auth, app, label=None, args=None, no_remove_on_fail=False):
     """
     Install apps
 
@@ -448,6 +448,7 @@ def app_install(auth, app, label=None, args=None):
         app -- Name, local path or git URL of the app to install
         label -- Custom name for the app
         args -- Serialize arguments for app installation
+        no_remove_on_fail -- Debug option to avoid removing the app on a filed installation
 
     """
     from yunohost.hook import hook_add, hook_remove, hook_exec
@@ -541,6 +542,7 @@ def app_install(auth, app, label=None, args=None):
         logger.exception(m18n.n('unexpected_error'))
     finally:
         if install_retcode != 0:
+            if not no_remove_on_fail:
                 # Setup environment for remove script
                 env_dict_remove = {}
                 env_dict_remove["YNH_APP_ID"] = app_id