[enh] Sandbox: also missing the `from` case

app/lib/dal/sqliteDAL/DocumentDAL.ts

 export interface DBDocument {
-  pubkey?: string
-  issuer?: string
-  issuers?: string[]
+  pubkey?: string     // idty table
+  from?: string       // cert table
+  issuer?: string     // membership table
+  issuers?: string[]  // txs table
 }
\ No newline at end of file

app/lib/dal/sqliteDAL/SandBox.ts

@@ -13,7 +13,9 @@ export class SandBox<T extends DBDocument> {
   }
   
   async acceptNewSandBoxEntry(element:T, pubkey:string) {
+    // Accept any document which has the exception pubkey (= the node pubkey)
     if (element.pubkey === pubkey
+      || element.from === pubkey
       || element.issuer === pubkey
       || (element.issuers !== undefined && element.issuers.indexOf(pubkey) !== -1)) {
       return true;