PowerShell script for automating dependency installation on Windows

[TheerapakG]

After creating your pull request, tick these boxes if they are applicable to you.

• [x] I have tested my changes against the review branch (the latest developmental version), and this pull request is targeting that branch as a base
• [x] I have tested my changes on Python 3.5.3 or higher

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Description

This PR adds install.ps1, which helps the user in getting dependencies similar to install.sh. However, unlike the install.sh, the script does not help user in setting up the bot as a service.

To try this out while this is still a PR use this command

Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; Invoke-Expression ((New-Object System.Net.WebClient).DownloadString('https://raw.githubusercontent.com/TheerapakG/MusicBot/playground_ps/install.ps1'));

in the PowerShell.

If this PR is merged into the review branch, change TheerapakG and playground_ps in the command to Just-Some-Bots and review Likewise, if this is merged into master then you can change TheerapakG and playground_ps in the command to Just-Some-Bots and master

Related issues (if applicable)