shortened hosts file URL creation + other tweaks

[jantari]

• refactored and shortened URL-string creation logic
• removed unneeded backticks (line-breaks after a pipe are always allowed)
• added "0.0.0.0" as the default value for the IP parameter instead of setting it later
• cleaned up regex IP replace and split up the pipeline (get-content and set-content in one pipeline isn't recommended because Get-Content may still have the file opened so Set-Content will fail to write it)
• replaced all occurences of

`"

(escaped double-quotes) with just ' (single quotes)

• replaced all instances of

Write-Host `n

with Write-Host "" as

`n

is technically only line-feed but Windows uses CRLF, I think it also looks nicer