Add section about non-support of symbols
Merge pull request #1 from gzm0/deprecate-symbol

Add section about non-support of symbols
Fix typo: s/TypeSafe/Typesafe/
Merge pull request #2 from adriaanm/patch-1

Fix typo: s/TypeSafe/Typesafe/
SVG logo.
Add big logo on front page.
Make the front-page logo more responsive.