update pacman.conf to match standard one

pacman.conf

@@ -1,3 +1,11 @@
+#
+# /etc/pacman.conf
+#
+# See the pacman.conf(5) manpage for option and repository directives
+
+#
+# GENERAL OPTIONS
+#
 [options]
 # The following paths are commented out with their default values listed.
 # If you wish to use different paths, uncomment and update the paths.
@@ -35,11 +43,56 @@ SigLevel    = Required DatabaseOptional
 LocalFileSigLevel = Optional
 #RemoteFileSigLevel = Required
 
+# NOTE: You must run `pacman-key --init` before first using pacman; the local
+# keyring can then be populated with the keys of all official Arch Linux
+# packagers with `pacman-key --populate archlinux`.
+
+#
+# REPOSITORIES
+#   - can be defined here or included from another file
+#   - pacman will search repositories in the order defined here
+#   - local/custom mirrors can be added here or in separate files
+#   - repositories listed first will take precedence when packages
+#     have identical names, regardless of version number
+#   - URLs will have $repo replaced by the name of the current repo
+#   - URLs will have $arch replaced by the name of the architecture
+#
+# Repository entries are of the format:
+#       [repo-name]
+#       Server = ServerName
+#       Include = IncludePath
+#
+# The header [repo-name] is crucial - it must be present and
+# uncommented to enable the repo.
+#
+
+# The testing repositories are disabled by default. To enable, uncomment the
+# repo name header and Include lines. You can add preferred servers immediately
+# after the header, and they will be used before the default mirrors.
+
+#[core-testing]
+#Include = /etc/pacman.d/mirrorlist
+
 [core]
 Include = /etc/pacman.d/mirrorlist
 
+#[extra-testing]
+#Include = /etc/pacman.d/mirrorlist
+
 [extra]
 Include = /etc/pacman.d/mirrorlist
 
-[community]
+# If you want to run 32 bit applications on your x86_64 system,
+# enable the multilib repositories as required here.
+
+#[multilib-testing]
+#Include = /etc/pacman.d/mirrorlist
+
+[multilib]
 Include = /etc/pacman.d/mirrorlist
+
+# An example of a custom package repository.  See the pacman manpage for
+# tips on creating your own repositories.
+#[custom]
+#SigLevel = Optional TrustAll
+#Server = file:///home/custompkgs