Add script to make a best guess at the url argument

[craig-landry]

Currently the setup needs the env var to be passed, which means a user needs to know their local ip. Ideally a script can figure that out.

Instead of running...

APP_URL=http://192.168.0.43:8000 docker-compose up

...I'd like to run

localaddress.sh

...and then that script does the work of running something like ip address and making a best guess at figuring out which network adapter is the "correct" one, or perhaps if it can't tell, prompting me with something like:

Which address should be used?
1) 192.168.0.29
2) 192.168.0.199
3) 172.17.0.1

It may not be super easy to figure out which is the most correct depending on what people have running though. Here's what my output looks like when I run ip address

➜  nginx-local-ip git:(main) ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: wlp0s20f3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 04:6c:59:f6:66:de brd ff:ff:ff:ff:ff:ff
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:cf:e2:4e brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:cf:e2:4e brd ff:ff:ff:ff:ff:ff
5: enxcc483ab6e737: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether cc:48:3a:b6:e7:37 brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.43/24 brd 192.168.0.255 scope global dynamic noprefixroute enxcc483ab6e737
       valid_lft 82905sec preferred_lft 82905sec
    inet6 fe80::a062:b5f8:f9cc:8df/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
6: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default 
    link/ether 02:42:10:38:f2:fb brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:10ff:fe38:f2fb/64 scope link 
       valid_lft forever preferred_lft forever
7: br-eb3c5a2ee416: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default 
    link/ether 02:42:ed:9b:d2:6b brd ff:ff:ff:ff:ff:ff
    inet 172.18.0.1/16 brd 172.18.255.255 scope global br-eb3c5a2ee416
       valid_lft forever preferred_lft forever
    inet6 fe80::42:edff:fe9b:d26b/64 scope link 
       valid_lft forever preferred_lft forever
9: veth892daa3@if8: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether d6:2f:2f:ea:5b:46 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::d42f:2fff:feea:5b46/64 scope link 
       valid_lft forever preferred_lft forever
11: veth100b359@if10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether ce:ac:fe:3d:30:a7 brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet6 fe80::ccac:feff:fe3d:30a7/64 scope link 
       valid_lft forever preferred_lft forever
13: veth200e5d0@if12: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether 9e:af:d9:25:b7:f7 brd ff:ff:ff:ff:ff:ff link-netnsid 2
    inet6 fe80::9caf:d9ff:fe25:b7f7/64 scope link 
       valid_lft forever preferred_lft forever
15: vetha0f1385@if14: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether be:71:4b:1e:40:c3 brd ff:ff:ff:ff:ff:ff link-netnsid 3
    inet6 fe80::bc71:4bff:fe1e:40c3/64 scope link 
       valid_lft forever preferred_lft forever
17: veth23dd43e@if16: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether e6:6d:a9:cd:e6:77 brd ff:ff:ff:ff:ff:ff link-netnsid 4
    inet6 fe80::e46d:a9ff:fecd:e677/64 scope link 
       valid_lft forever preferred_lft forever
19: vethba0bf8b@if18: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-eb3c5a2ee416 state UP group default 
    link/ether 76:cb:95:f1:2f:17 brd ff:ff:ff:ff:ff:ff link-netnsid 5
    inet6 fe80::74cb:95ff:fef1:2f17/64 scope link 
       valid_lft forever preferred_lft forever