Fixes #2498 - Updated documentation for Windows users

[softvision-oana-arbuzov]

Updated documentation with needed requirements (programs, extra settings and file updates).

This PR fixes issue #2498

Proposed PR background

Please provide enough information so that others can review your pull request:

• "Git" needs to be installed
• "tmp" needs to be changed in "temp" in init.py file

---

• I have read the Pull Request + Code Style Guidelines thoroughly.

[TravisBuddy]

Travis tests have failed

Hey @softvision-oana-arbuzov,
Please read the following log in order to understand the failure reason.
It'll be awesome if you fix what's wrong and commit the changes.

1st Build

nosetests

Milestones are not initialized. Check logs.

npm run test:js -- --reporters="runner" --firefoxBinary=`which firefox`

> webcompat@ test:js /home/travis/build/webcompat/webcompat.com
> node ./tests/functional/_intern.js "--reporters=runner" "--firefoxBinary=/home/travis/firefox-58.0/firefox/firefox"

Error: 
        ======================================================
        Oops, something went wrong. Try restarting the server.
        Open another terminal and window type:
        npm run start:test
        or
        python run.py -t
        ======================================================
        
  at ClientRequest.<anonymous>  <tests/functional/lib/setup.js:55:9>
  at emitOne  <events.js:116:13>
  at ClientRequest.emit  <events.js:211:7>
  at Socket.socketErrorListener  <_http_client.js:387:9>
  at emitOne  <events.js:116:13>
  at Socket.emit  <events.js:211:7>
  at emitErrorNT  <internal/streams/destroy.js:64:8>
something bad happened inside intern.run()
{ Error: 
        ======================================================
        Oops, something went wrong. Try restarting the server.
        Open another terminal and window type:
        npm run start:test
        or
        python run.py -t
        ======================================================
        
    at ClientRequest.<anonymous> (/home/travis/build/webcompat/webcompat.com/tests/functional/lib/setup.js:55:9)
    at emitOne (events.js:116:13)
    at ClientRequest.emit (events.js:211:7)
    at Socket.socketErrorListener (_http_client.js:387:9)
    at emitOne (events.js:116:13)
    at Socket.emit (events.js:211:7)
    at emitErrorNT (internal/streams/destroy.js:64:8)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9) reported: true }
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! webcompat@ test:js: `node ./tests/functional/_intern.js "--reporters=runner" "--firefoxBinary=/home/travis/firefox-58.0/firefox/firefox"`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the webcompat@ test:js script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/travis/.npm/_logs/2018-06-18T14_39_12_329Z-debug.log