feat: generic partition brick with filetype detection

[MthwRobinson]

Summary

Adds a generic partition brick that detects the file type and then invokes the appropriate partitioning brick. In support of this functionality, this PR also adds the following:

• A module for detecting file type
• Includes magic in the dependencies and instructions for installing libmagic
• Added support for processing file-like objects in "rb" mode to partition_html and partition_eml

Testing

  import docx
  from unstructured.partition.auto import partition

  document = docx.Document()
  document.add_paragraph("Important Analysis", style="Heading 1")
  document.add_paragraph("Here is my first thought.", style="Body Text")
  document.add_paragraph("Here is my second thought.", style="Normal")
  document.save("mydoc.docx")
  elements = partition(filename="mydoc.docx")

  with open("mydoc.docx", "rb") as f:
      elements = partition(file=f)

  from unstructured.partition.auto import partition
  elements = partition(filename="example-docs/layout-parser-paper-fast.pdf")

[MthwRobinson]

Test failure is due to libmagic detecting different MIME types for .docx and .xlsx files on Mac vs. Linux (see this issue for details). Currently working a fix.

[cragwolfe]

Also need to add support in the Dockerfile? I believe the package is file-devel

[MthwRobinson]

Per offline convo, I'm removing the dockerfile since we're not using that for anything

[qued]

Suggested change

	install-ci: install-base-pip-packages install-test install-nltk-models install-huggingface install-unstructured-inference local-inference
	install-ci: install-base-pip-packages install-test install-nltk-models install-huggingface install-unstructured-inference install-local-inference