tinymce的bug修改

测试提了几个bug：
1.默认的字体单位是pt，修改为px
2.默认字体大小18px
3.字体要有微软雅黑，宋体，黑体
4.行间距可以配置
5.默认行间距line-height:1.75，段落间距要比行间距大一些

在前端页面，加入默认样式：

.article >>> p {
    margin: 15px 0;
    border: 0px;
    padding: 0px;
    line-height: 1.75;
    font-size: 18px;
}

后端代码：

import tinymce from 'tinymce/tinymce'
import 'tinymce/themes/modern/theme'
import Editor from '@tinymce/tinymce-vue'
import 'tinymce/plugins/image'
import 'tinymce/plugins/imagetools'
import 'tinymce/plugins/link'
import 'tinymce/plugins/code'
import 'tinymce/plugins/table'
import 'tinymce/plugins/lists'
import 'tinymce/plugins/contextmenu'
import 'tinymce/plugins/wordcount'
import 'tinymce/plugins/colorpicker'
import 'tinymce/plugins/textcolor'
import 'tinymce/plugins/preview'

import { train } from '../../api/index' // 接口
import { startLoading, endLoading } from '../../common/js/until' // 公共方法

export default {
    data() {
        return {
            editorInit: {
                content_style: "p {margin: 15px 0; border:0px ; padding: 0px;line-height:1.75;font-size:18px;};",
                language_url: require('./zh_CN.js'),
                language: 'zh_CN',
                skin_url: './../../../static/tinymce/skins/lightgray',
                height: 300,
                automatic_uploads: true,
                plugins: 'link lists image imagetools code table colorpicker textcolor wordcount contextmenu preview ',
                toolbar: ' fontselect fontsizeselect | forecolor backcolor styleselect | bold italic underline strikethrough  | alignleft aligncenter alignright alignjustify | bullist numlist | outdent indent blockquote | undo redo | link unlink image media table code | removeformat | preview',
                style_formats: [
                    {
                        title: "行间距", items: [
                            { title: '1', block: 'p', styles: { 'line-height': '1.0' } },
                            { title: '1.5', block: 'p', styles: { 'line-height': '1.5' } },
                            { title: '1.75', block: 'p', styles: { 'line-height': '1.75' } },
                            { title: '2', block: 'p', styles: { 'line-height': '2' } },
                            { title: '3', block: 'p', styles: { 'line-height': '3' } },
                            { title: '4', block: 'p', styles: { 'line-height': '4' } },
                            { title: '5', block: 'p', styles: { 'line-height': '5' } },
                        ]
                    },
                ],
                style_formats_merge: true,
                fontsize_formats:'10px 11px 12px 13px 14px 15px 16px 18px 20px 22px 24px 26px 28px 32px',
                font_formats:'宋体=宋体;黑体=黑体;仿宋_GB2312=仿宋_GB2312;楷体_GB2312=楷体_GB2312;隶书=隶书;幼圆=幼圆;微软雅黑=microsoft yahei;Andale Mono=andale mono,monospace;' + 'Arial=arial,helvetica,sans-serif;' + 'Arial Black=arial black,sans-serif;' + 'Book Antiqua=book antiqua,palatino,serif;' + 'Comic Sans MS=comic sans ms,sans-serif;'  + 'Helvetica=helvetica,arial,sans-serif;',
                images_upload_handler: (blobInfo, success, failure) => {}

   image_class_list: [
                    {title: '最大宽度为100%', value: 'img-responsive'}, 
                    {title: '强制设置宽度为100%', value: 'img-responsive'}, 
                    {title: '宽高由上面的数值大小设置', value: ''},
                ],