Wiki links with anchor reference, MultiMarkdown style footnotes and fix for inline code mistaken for fence startMul

[vsch]

update test.

Not critical for most since no one complained about it. I only noticed it because I am testing the plugin.

[vsch]

Added fixes for #203 and #204

[vsch]

Could not get the tests to pass no matter how the expected text was defined. The actual always had \n\n after <br> and expected did not. Found that for some reason Tidy has this peculiar effect and I did not feel like diving into Tidy() code.

[sirthias]

Yes, tidy is not perfect.
Some of the tests certainly depend on some of it's quirks, so please feel free to adapt the test however you see fit.

[vsch]

PHP Markdown Extra style footnotes added. Opted out for PHP Markdown Extra not the MultiMarkdown ones. Did not see the need for long footnote names. Can be changed if someone desires alphanumeric footnote references instead of integers.

I did not include this extension in the ALL extensions flags to avoid having to potentially rework existing tests. Anyone who wants this extension will need to add the flag to Extensions.ALL.

Tests added for both with and without extension parsing of markdown with footnotes.

I also bit the bullet and ran the IntelliJ reformat code command on the parser code so that it is uniformly formatted and without trailing blanks otherwise every commit to master I would have to go through the chunks and discard format only ones.

[vsch]

Changed footnotes to be MultiMarkdown style. Footnote labels now allow alphanumeric, dash, dot, underscore. The rendered footnotes are sequential integers as before.

Tests updated.

This fixes #140.