Updated snippets for javascript
Removed visual adhoc snippets (I never use them)

It's probably better to just use <leader>es to make some real snippets
on the fly and then delete them later if you want to (or not, doesn't
really matter too much). I wish I used snippets like this more so I'll
give it a go. A lot of the time it's a cleaner alternative to using
macros or copy/pasting an entry and then changing it selectively.