Markdown Filter: translating indented code blocks should be optional

[Chase Tingley]

The attached file contains the same code block represented two ways: as a fenced code block, and as an indented code block.

These are both code blocks, however our handling of them is inconsistent:

• fenced code blocks are optionally extracted, depending on the value of the “Translate Fenced Code Blocks” option.
• indented code blocks are always extracted.

The filter should support an option to make translation of indented code blocks optional.

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[Chase Tingley]

Fixed by https://bitbucket.org/okapiframework/okapi/pull-requests/548