Correct ES6 syntax grammer.

Most of corrections are markup correction.

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Correct PrimaryExpression.

RegularExpressionLiteral is missing in PrimaryExpression.

Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
Merge pull request #4 from omasanori/revise

Correct ES6 syntax grammer.