DocxParser need more "markdown style"

[zakahan]

Two engines of DocParser, pandoc and xml, do not produce markdown text that is very "markdown-style".
The output for headings by pandoc is bold markup, instead of ### heading level, and the syntax for table output also seems to be a custom syntax rather than the standard markdown table.
The xml method, seems to convert the document into plain text and tables, without any ### heading levels.