move wellKnownJson to domains

after some more thought:
* If app moves to another location, user has to remember to move all this config
* It's not really associated with an app. It's to do with the domain info
* We can put some hints in the UI if app is missing.

part of #703

migrations/schema.sql

@@ -86,7 +86,6 @@ CREATE TABLE IF NOT EXISTS apps(
     taskId INTEGER, // current task
     errorJson TEXT,
     servicesConfigJson TEXT, // app services configuration
-    wellKnownJson TEXT,
     containerIp VARCHAR(16) UNIQUE, // this is not-null because of ip allocation fails, user can 'repair'
 
     FOREIGN KEY(mailboxDomain) REFERENCES domains(domain),
@@ -149,6 +148,7 @@ CREATE TABLE IF NOT EXISTS domains(
     provider VARCHAR(16) NOT NULL,
     configJson TEXT, /* JSON containing the dns backend provider config */
     tlsConfigJson TEXT, /* JSON containing the tls provider config */
+    wellKnownJson TEXT, /* JSON containing well known docs for this domain */
 
     PRIMARY KEY (domain))