Removed unused add/edit methods from integrations

refs 17feb14e4a

- The original commit adding this intended to add transactions, following the pattern of always forcing a transaction when we use bookshelf-relations
- (We use bookshelf-relations here because integrations have api-keys and webhooks associated wtih them and we upsert as one)
- These add and edit methods were inadvertently added to the wrong argument object/section of bookshelf (really fucking easily done, one day we will fix bookshelf so its easier to work with)
- Bottom line: these methods have never been called
- I tried moving them to the right section, but this created test failures throughout our acceptance tests:
   - Error: Transaction query already complete, run with DEBUG=knex:tx for more info
- This is likely because we need to account for integrations being used as part of the auth step in the before part of tests
- In terms of yak-shaving, fixing these tests is one step too far right now. I think not having this code here at all is a better state than having it look like it works when it doesn't

core/server/models/integration.js

@@ -21,44 +21,6 @@ const Integration = ghostBookshelf.Model.extend({
         ghostBookshelf.Model.prototype.emitChange.bind(this)(this, eventToTrigger, options);
     },
 
-    add(data, options) {
-        const addIntegration = () => {
-            return ghostBookshelf.Model.add.call(this, data, options)
-                .then(({id}) => {
-                    return this.findOne({id}, options);
-                });
-        };
-
-        if (!options.transacting) {
-            return ghostBookshelf.transaction((transacting) => {
-                options.transacting = transacting;
-
-                return addIntegration();
-            });
-        }
-
-        return addIntegration();
-    },
-
-    edit(data, options) {
-        const editIntegration = () => {
-            return ghostBookshelf.Model.edit.call(this, data, options)
-                .then(({id}) => {
-                    return this.findOne({id}, options);
-                });
-        };
-
-        if (!options.transacting) {
-            return ghostBookshelf.transaction((transacting) => {
-                options.transacting = transacting;
-
-                return editIntegration();
-            });
-        }
-
-        return editIntegration();
-    },
-
     onSaving(integration, attrs, options) {
         ghostBookshelf.Model.prototype.onSaving.apply(this, arguments);