Add support for a required proxy on install target system.

[william-stearns]

Update install_pre.yml to add support for installing to a system that requires the use of a proxy. Note that there are no changes needed for install_post.yml .

[william-stearns]

Note: commit 490c554 has not been tested.

[william-stearns]

As a side note, I've written the text that will go in the user guide to support these commits. I'm pasting that text below for your reference (but not asking you to take responsibility for putting it in the guide.)

        If the systems to which you're installing AC-Hunter can only
reach the Internet through a proxy you'll have to tell ansible how to
use it.  Before running the installer, run the following commands on the
system from which you run the installer.

        If your proxy is located on the host system on which AC-Hunter
will be run, run the following 2 commands, substituting the proxy port
for 3128, then run ./install_achunter.sh as normal:

export ans_http_proxy='http://172.17.0.1:3128'
export ans_https_proxy='http://172.17.0.1:3128'
#Now run ./install_achunter.sh achunter_hostname

        If your proxy is located on some other system run the following
(substituting that system's hostname or IP for myproxyhost and the port
number for 3128).  Make sure the AC-Hunter system can reach the proxy.

export ans_http_proxy='http://myproxyip:3128'
export ans_https_proxy='http://myproxyip:3128'
#Now run ./install_achunter.sh achunter_hostname

        If your proxy requires a username and password for access AND
you're on a Debian or Ubuntu system, you can place those after the two
forward slashes like this:
export ans_http_proxy='http://the_username:the_password@172.17.0.1:3128'
export ans_https_proxy='http://the_username:the_password@172.17.0.1:3128'
        or
export ans_http_proxy='http://the_username:the_password@myproxyip:3128'
export ans_https_proxy='http://the_username:the_password@myproxyip:3128'

        If your proxy requires a username and password for access AND
you're on an rpm-based system, you will need to add the following two
lines to /etc/dnf/dnf.conf on the AC-Hunter system by hand before
running the two export commands and running the install:
proxy_username=the_username
proxy_password=the_password

        These changes support apt (and equivalent tools like apt-get) on
Ubuntu and Debian.  They also support Alma Linux, Centos, RedHat
Enterprise, Oracle, and Rocky 8 and above.  They also support Fedora 22
and above.  Note that only the most recent versions of Rocky, Centos,
and Ubuntu have been tested.

[0x6d6f7468]

Note: commit 490c554 has not been tested.

Is there a reason why this commit hasn't been tested? Just curious, and making sure the PR is ready to review. Thanks!

[william-stearns]

Note: commit 490c554 has not been tested.

Is there a reason why this commit hasn't been tested? Just curious, and making sure the PR is ready to review. Thanks!

My apologies - I forgot that the testing for the rpm/dnf commit had not been done. I'll test it now. (Note, the apt side was already tested.)