Added notes to block-level function declaration

Just some notes clarifying that this feature was indeed discouraged in
ES5, in case people are confused by its inclusion in the ES6 table.
Fixed whitespace in HTML files
Fixed syntax error in Symbol.hasInstance test

Accidentally used "class" as an identifier.
Merge pull request #242 from webbedspace/hasinstance

Fixed a syntax error in Symbol.hasInstance test
Merge pull request #238 from webbedspace/blockfunction-note

Added notes to block-level function declaration
Merge pull request #235 from webbedspace/gh-pages

Fixes ES5 and non-standard pages in IE 8
Fixed a minor bug
Fixed cell highlighting in non-standard table
Fixed the non-standard "obsolete" checkbox
Removed a certain message