Fixed "Save as HTML" to respect blockquotes.

When saving as HTML, the raw text was being HTML escaped prior to
running it through markdown. This was preventing blockquotes from
rendering because greater-than signs were escaped. The HTML escaping
seems unneeded since the markdown renderer already takes care of it,
and it also wasn't consistent with how markdown was being rendered
within the application.

browser/components/MarkdownPreview.js

@@ -16,7 +16,6 @@ import convertModeName from 'browser/lib/convertModeName'
 import copy from 'copy-to-clipboard'
 import mdurl from 'mdurl'
 import exportNote from 'browser/main/lib/dataApi/exportNote'
-import { escapeHtmlCharacters } from 'browser/lib/utils'
 import context from 'browser/lib/context'
 import i18n from 'browser/lib/i18n'
 import fs from 'fs'
@@ -325,9 +324,7 @@ export default class MarkdownPreview extends React.Component {
         allowCustomCSS,
         customCSS
       )
-      let body = this.markdown.render(
-        escapeHtmlCharacters(noteContent, { detectCodeBlock: true })
-      )
+      let body = this.markdown.render(noteContent)
       const files = [this.GetCodeThemeLink(codeBlockTheme), ...CSS_FILES]
       const attachmentsAbsolutePaths = attachmentManagement.getAbsolutePathsOfAttachmentsInContent(
         noteContent,