Alerts Component

#### Alerts:

The alerts component provide contextual feedback messages for typical user actions with the handful of available and flexible alert messages.

Base specifications: bootstrap 3 or bootstrap 4.

This directive can be used to generate alerts from the dynamic model data (using the `ng-for` directive).

#### New Alert:

Alert message: Alert type:
Closable:
Dismiss time(s):

#### Alerts Lists:

{{ alert?.message }}

#### Example Code:

                 // Alerts template
                 <alert *ngFor="let alert of alerts;let i = index" [type]="alert.type" [dismissible]="alert.closable" [dismissOnTimeout]="alert.dismissTime" (close)="closeAlert(i)">{ { alert?.message } }</alert>

                 // Add new alert button
                 <button type="button" class='btn btn-sm btn-primary mr-t-20' (click)="addAlert()">Add Alert</button>

                 // Add new alert function
                 public addAlert():void {
                   this.alertObj.closable = (this.alertObj.closable === true || this.alertObj.closable === 'true');
                   this.alertObj.dismissTime < 0 ? this.alertObj.dismissTime = 0 : this.alertObj.dismissTime;

                   this.alerts.push({
                     message: this.alertObj.message,
                     type: this.alertObj.type,
                     closable: this.alertObj.closable,
                     dismissTime: this.alertObj.dismissTime * 1000
                   });
                 }

#### Alert properties:

- `type` (`?:string='warning'`) - provide one of the four supported contextual classes:`success`,`info`, `warning`, `danger`
- `dismissible` (`?:boolean=false`) - determines if an inline close button is displayed
- `dismissOnTimeout` (`?number=0`) - number of milliseconds, if specified sets a timeout duration, after which the alert will be closed

#### Alert events:

- `close` - fired when `alert` closed with inline button or by timeout, `$event` is an instance of `Alert` component