Add handling of jpx image decoding

[fgregg]

Pull request

This PR adds handling for the JPXDecode filter, as suggested in #163 (comment). This allows extraction of images from pdfs that use this filter

Will fix #163

How Has This Been Tested?

Tested locally. Images extracted correctly. Unfortunately, I do not have non-proprietary pdfs to share.

Checklist

• I have added tests that prove my fix is effective or that my feature
  works
• I have added docstrings to newly created methods and classes
• I have optimized the code at least one time after creating the initial
  version
• I have updated the README.md or I am verified that this
  is not necessary
• I have updated the readthedocs documentation or I
  verified that this is not necessary
• I have added a consice human-readable description of the change to
  CHANGELOG.md

[jangxyz]

Any updates on this? Reached to the exact same fix as this PR. Is there any specific reason why this PR is on hold?

[pietermarsman]

PIL is used without it being in the requirements. Created #701 for this.

[pietermarsman]

Had to merge with command line due to conflict: 708dd20

[pietermarsman]

@fgregg thanks for the work. @jangxyz Thanks for the review.