- Refactoring of the mail sending part. Mail queue (table 'queued') is now used also for all test emails.

- More options how to send test emails.
- Fixed problems with pausing a campaign (#593)
- Started rework of transactional sender of templates (#606), however this contains functionality regression at the moment because it does not interpret templates as HBS. It needs HBS option for templates as described in https://github.com/Mailtrain-org/mailtrain/issues/611#issuecomment-502345227

TODO:
- detect sending errors connected to not able to contact the mailer and pause/retry campaing and queued sending - don't mark the recipients as BOUNCED
- add FAILED campaign state and fall into it if sending to campaign consistently fails (i.e. the error with sending is not temporary)
- if the same happends for queued email, delete the message

client/src/templates/CUD.js

@@ -27,7 +27,7 @@ import {getEditForm, getTemplateTypes, getTypeForm} from './helpers';
 import axios from '../lib/axios';
 import styles from "../lib/styles.scss";
 import {getUrl} from "../lib/urls";
-import {TestSendModalDialog} from "./TestSendModalDialog";
+import {TestSendModalDialog, TestSendModalDialogMode} from "../campaigns/TestSendModalDialog";
 import {withComponentMixins} from "../lib/decorator-helpers";
 import moment from 'moment';
 
@@ -298,6 +298,7 @@ export default class CUD extends Component {
             <div className={this.state.elementInFullscreen ? styles.withElementInFullscreen : ''}>
                 {isEdit &&
                     <TestSendModalDialog
+                        mode={TestSendModalDialogMode.TEMPLATE}
                         visible={this.state.showTestSendModal}
                         onHide={() => this.setState({showTestSendModal: false})}
                         getDataAsync={this.sendModalGetDataHandler}/>