Generated function expression should have `expression: false`

Currently generated `FunctionExpression` contains `expression: true` which is ES6-only property intended to be used for arrow functions which contain single expression as body (instead of block).

This confuses `escodegen` which tries to generate single expression from function's body but finds `BlockStatement` thus failing with `Error: Unknown expression type: BlockStatement`.
Update the change log for v0.4.3 through v0.8.0.
Remove unnecessary parameter to getEnclosingNodeOfType.
Add missing param doc comment.
Reformat some function declarations.
Merge remote-tracking branch 'RReverser/patch-1'

* RReverser/patch-1:
  Generated function expression should have `expression: false`
v0.8.1