Changes so that it works on windows

[tansherjun]

It turns out that WIndows does weird things to the *sh script (I think it may add CRLF instead of preserving the LF) so what I found out the hard way was the the mv command to move the codeigniter folder into the /var/www/html foder never occurred and it must be due to the way windows decides to change LF to CRLF when I clone the repo.

So what I have done is

• create the .sh file in the dockerfile itself instead of having to use the ADD command (this makes it works on Docker Desktop on WIndows)
• Changed the docker-compose yml to just use the local build context instead.