Parsedown ignores multiple line breaks inside pre/code

[gabrielbarros]

For example:

This is a test

    function test1() {

    }





    function test2() {

    }

---

Expected output:

Given output:

[aidantwoods]

Not yet released, but 2.0 will the number of line breaks that occurred properly (rather than just whether or not a line break occurred), so going to close this. This is also fixed in #610, and is fixed in the beta releases of 1.8.x (but this version won't be released in non-beta due to compatibility concerns with extensions).