Steganalysis Scanners

[phutelmyer]

Describe the change
Modifications of PR: #206

Implements steganalysis scanners. For more information, please see above PR.

Describe testing procedures
Obtained various images utilizing steganography techniques (e.g., least significant bit, end of file, noise floor) and tested against developed scaners.

Sample output
New scanner output example:

    "lsb": {
      "elapsed": 0.007413,
      "lsb": false
    },
    "nf": {
      "elapsed": 0.00739,
      "noise_floor": true,
      "percentage": 0.0000013857363387183047,
      "threshold": 0.25
    },
    "ocr": {
      "elapsed": 0.737444,
      "text": [
        "This",
        "image",
        "totally",
        "doesn't",
        "have",
        "any",
        "hidden",
        "messages.",
        "zrbj",
        "zrbj"
      ]
    },
    "png_eof": {
      "PNG_EOF": "\r\nQuick! Look Behind you! There's absolutely noting unusual there!",
      "elapsed": 0.00012,
      "trailer_index": 48644
    },

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of and tested my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings