Update docs with better config + installation instructions (#300)

* start reworking some documentation

* fuller documentation  + better docs structure

docs/configuration/general.md

@@ -1,3 +1,67 @@
 # General
 
-TODO
+The top-level configuration for GoToSocial, including basic things like host and transport protocol.
+
+The only things you *really* need to set here are `host`, which should be the hostname where your instance is reachable, and probably `port`.
+
+## Settings
+
+```yaml
+###########################
+##### GENERAL CONFIG ######
+###########################
+
+# String. Log level to use throughout the application. Must be lower-case.
+# Options: ["trace","debug","info","warn","error","fatal"]
+# Default: "info"
+logLevel: "info"
+
+# String. Application name to use internally.
+# Examples: ["My Application","gotosocial"]
+# Default: "gotosocial"
+applicationName: "gotosocial"
+
+# String. Hostname that this server will be reachable at. Defaults to localhost for local testing,
+# but you should *definitely* change this when running for real, or your server won't work at all.
+# DO NOT change this after your server has already run once, or you will break things!
+# Examples: ["gts.example.org","some.server.com"]
+# Default: "localhost"
+host: "localhost"
+
+# String. Domain to use when federating profiles. This is useful when you want your server to be at
+# eg., "gts.example.org", but you want the domain on accounts to be "example.org" because it looks better
+# or is just shorter/easier to remember.
+# To make this setting work properly, you need to redirect requests at "example.org/.well-known/webfinger"
+# to "gts.example.org/.well-known/webfinger" so that GtS can handle them properly.
+# You should also redirect requests at "example.org/.well-known/nodeinfo" in the same way.
+# An empty string (ie., not set) means that the same value as 'host' will be used.
+# DO NOT change this after your server has already run once, or you will break things!
+# Examples: ["example.org","server.com"]
+# Default: ""
+accountDomain: ""
+
+# String. Protocol to use for the server. Only change to http for local testing!
+# This should be the protocol part of the URI that your server is actually reachable on. So even if you're
+# running GoToSocial behind a reverse proxy that handles SSL certificates for you, instead of using built-in
+# letsencrypt, it should still be https.
+# Options: ["http","https"]
+# Default: "https"
+protocol: "https"
+
+# Int. Listen port for the GoToSocial webserver + API. If you're running behind a reverse proxy and/or in a docker,
+# container, just set this to whatever you like (or leave the default), and make sure it's forwarded properly.
+# If you are running with built-in letsencrypt enabled, and running GoToSocial directly on a host machine, you will
+# probably want to set this to 443 (standard https port), unless you have other services already using that port.
+# This *MUST NOT* be the same as the letsencrypt port specified below, unless letsencrypt is turned off.
+# Examples: [443, 6666, 8080]
+# Default: 8080
+port: 8080
+
+# Array of string. CIDRs or IP addresses of proxies that should be trusted when determining real client IP from behind a reverse proxy.
+# If you're running inside a Docker container behind Traefik or Nginx, for example, add the subnet of your docker network,
+# or the gateway of the docker network, and/or the address of the reverse proxy (if it's not running on the host network).
+# Example: ["127.0.0.1/32", "172.20.0.1"]
+# Default: ["127.0.0.1/32"] (localhost)
+trustedProxies:
+  - "127.0.0.1/32"
+```