Rename 'main' doctree to 'www'; refactor sphinx task conf

tasks.py

@@ -1,16 +1,23 @@
+from os.path import join
+
 from invoke import Collection
-from invocations import docs, testing
+from invocations import docs as _docs, testing
 
 
-# Usage doc/API site
-api = Collection.from_module(docs, name='docs', config={
-    'sphinx.source': 'sites/docs',
-    'sphinx.target': 'sites/docs/_build',
-})
-# Main/about/changelog site
-main = Collection.from_module(docs, name='main', config={
-    'sphinx.source': 'sites/main',
-    'sphinx.target': 'sites/main/_build',
+d = 'sites'
+
+# Usage doc/API site (published as docs.paramiko.org)
+path = join(d, 'docs')
+docs = Collection.from_module(_docs, name='docs', config={
+    'sphinx.source': path,
+    'sphinx.target': join(path, '_build'),
 })
 
-ns = Collection(testing.test, docs=api, main=main)
+# Main/about/changelog site ((www.)?paramiko.org)
+path = join(d, 'www')
+www = Collection.from_module(_docs, name='www', config={
+    'sphinx.source': path,
+    'sphinx.target': join(path, '_build'),
+})
+
+ns = Collection(testing.test, docs=docs, www=www)