Updated usage information for runtests.pl

As this is how it introduces itself when run without parameters and also how it works properly.

```
$ perl runtests.pl
runtests.pl SPEC PROGRAM
Set ANSI_COLORS_DISABLED=1 if you redirect to a file.
Set PATT='...' to restrict tests to sections matching a regex.
```
Fix the output of the JS `markdown` executable.

Previously, because of `console.log` semantics, if you ran:

```
make test PROG=js/markdown
```

You'd get a couple of errors caused by `console.log` calls putting `\n`
line breaks where they shouldn't. This fixes that by using
`process.stdout.write` instead of `console.log`.

This isn't something really important, but it's nice for all the
provided executables to pass the test suite.
Make fenced code blocks add the `class`to `code` rather than `pre` 

This matches the convention set out in the HTML Living Standard (http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-code-element) and makes existing syntax highlighting scripts recognize the programming language used.

Ref. http://talk.standardmarkdown.com/t/fenced-code-blocks-should-add-class-to-code-rather-than-pre-matching-the-html-best-practice/136
Minor fixes - non messed-up version!



A few undeclared variables - no big deal there. One use of block_end_line where block.end_line was meant (I believe).

Also - query as to whether the new keyword is needed when calling InlineParser as the function returns an object, so we're not dealing with an instance of InlineParser (I haven't changed this, just a query).
Update stmd.js
replace Standard Markdown with CommonMark
Merge pull request #86 from ousia/master

replace Standard Markdown with CommonMark
Cosmetic change in README.
Updated date in spec.
Capitalize Markdown.
Merge pull request #81 from BurtHarris/master

Resolve test.js line-ending sensitivity blocking running tests on Windows
Merge pull request #77 from Steve-Fenton/patch-1

Minor fixes to stmd.js (non messed-up version)
Merge pull request #71 from mathiasbynens/patch-1

Make fenced code blocks add the `class` to `code` rather than `pre`
Adjusted HTML output for fenced code to match #71 change.
Merge pull request #65 from yamadapc/master

Fix the output of the JS `markdown` executable.
Fixed extra space before period.

This is @robinst's fix in #20, which couldn't be merged
automatically.  Thanks, @robinst.
Merge pull request #54 from cebe/patch-1

Updated usage information for runtests.pl
More capitalizing Markdown.
Added anchor to linkDestination regexes.

Closes #62.
stmd.js:  Added another regex anchor, in reMain.