Add support for LaTeX inline and block expressions. (#4446)

* Add support for LaTeX inline and block expressions. (#4364)

Co-authored-by: Tom Moor <tom@getoutline.com>

* tsc

* Show heading markers when LaTeX block is being edited

* Tab to space, name katex chunk

* Fork htmldiff, add support for math nodes

Co-authored-by: luisbc92 <luiscarlos.banuelos@gmail.com>

shared/i18n/locales/en_US/translation.json

@@ -277,6 +277,8 @@
   "Bold": "Bold",
   "Subheading": "Subheading",
   "Table": "Table",
+  "Math inline (LaTeX)": "Math inline (LaTeX)",
+  "Math block (LaTeX)": "Math block (LaTeX)",
   "Tip": "Tip",
   "Tip notice": "Tip notice",
   "Show diagram": "Show diagram",
@@ -571,7 +573,9 @@
   "Numbered list": "Numbered list",
   "Blockquote": "Blockquote",
   "Horizontal divider": "Horizontal divider",
+  "LaTeX block": "LaTeX block",
   "Inline code": "Inline code",
+  "Inline LaTeX": "Inline LaTeX",
   "Sign In": "Sign In",
   "Continue with Email": "Continue with Email",
   "Continue with {{ authProviderName }}": "Continue with {{ authProviderName }}",