Refactor Package structure

This commit cleans up the package structure, to make two new top-level
packages `internal` (for internal-use packages) and `pkg` (for general
shared utility code).

env/instances/barrel/conf/wisski.conf

@@ -1,24 +0,0 @@
-<VirtualHost *:8080>
-    # the document root -- /var/www/data/project/web
-    DocumentRoot /var/www/data/project/web
-
-    <Directory /var/www/data/project/web>
-        # add types for .owl and .rdf
-        AddType application/rdf+xml .owl
-        AddType application/rdf+xml .rdf
-
-        # Rewrite the 'ontology' directory
-        RewriteEngine On
-        RewriteOptions InheritDownBefore
-        ReWriteRule ^(ontology/[^/]+/).+ $1 [R=303,END]
-        ReWriteRule ^(ontology/[^/]+)/$ sites/default/files/$1.owl [END]
-
-        # Allow overrides of symlinks
-        Options Indexes FollowSymLinks
-        AllowOverride All
-        Require all granted
-    </Directory>
-
-    ErrorLog /dev/stderr
-    CustomLog /dev/stdout combined
-</VirtualHost>