Enable HTTP 30x redirections in curl requests (fix issue #589)

[sphakka]

Enable HTTP 30x redirections in curl requests -- fix issue #589:

• curl: enable a configurable number of redirections (-redirects=<max>) to follow when making HTTP(S) requests.
• docs: update Infomaniak example to prefer 'dyndns2' instead of obsolete protocol.

Test

F.i., with Infomaniak:

$ cat > /tmp/ddclient.conf <<EOF
pid=/tmp/ddclient.pid           
ssl=yes

protocol=dyndns2
use=web, web=infomaniak.com/ip.php/
server=infomaniak.com
login=$login
password=$password
# uncomment to test without CLI option -redirect
#redirect=2
$host      
EOF

Then:

$ ddclient -file=/tmp/ddclient.conf -daemon=0 -debug -verbose -noquiet -redirect=2

[LenardHess]

Merged 👍

For any future pull request, please separate different changes into separate commits or even separate pull requests.
I.e. in the PR we had changes to curl, changes to Infomaniak and random whitespace cleanup - all of which are not related. This makes it more tedious to traverse the history later.