Add Windows installation instructions for pdf2searchablepdf

[ElectricRCAircraftGuy]

I need to get it working in Windows, and document how.

Sample start to the documentation:

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Windows Installation Instructions for pdf2searchablepdf

Tested in Windows 10 running in Virtual Box virtual machine inside Ubuntu 20.04.

1. Install Git for Windows:
   1. Go to https://git-scm.com/download/win --> click "64-bit Git for Windows Setup" (or whatever you need for your system). Download and install it.

[p-elsie]

This works perfectly on Ubuntu 20.04 on WSL. Just use the Ubuntu instructions, except:

1. Install WSL (Windows Subsystem for Linux) with Ubuntu dist
2. Where it says, sudo apt install tesseract-ocr, instead use sudo apt install tesseract-ocr poppler-utils

A normal Ubuntu dist will include poppler-utils, but the WSL image does not.

[ElectricRCAircraftGuy]

@p-elsie , thank you! I need to add that information into my main readme. This is super useful for other Windows users. I'm glad to hear it works there!

[ElectricRCAircraftGuy]

I'll leave this issue open until I add this information to the main readme.