Update instructions for handling new folders.

Author: tabatkins

.htaccess

@@ -80,14 +80,34 @@ RewriteRule ^css4-text/(.*)$ http://dev.w3.org/csswg/css-text-4/$1 [R=301,L]
 # and the numbered urls as tagged branches.
 # Except for exceptional circumstances, 
 # always work in unversioned folders.
-# `hg copy` the folder into a versioned name when you publish CR, 
+#
+# Every unversioned folder needs a corresponding line here,
+# redirecting the appropriate versioned url to the unversioned folder.
+#
+# When you hit CR with one level and wish to start editting a new level,
+# `hg copy` the current unversioned folder into a versioned one, 
 # and update the rule below to n+1,
 # so you can start work on the next level in an unversioned folder.
+# That is, if you're current editting Foo level 3 in a css-foo folder,
+# and it's hit CR and you'd like to start working on Foo level 4,
+# run `hg copy css-foo css-foo-3`,
+# then update the line below from css-foo-3 to css-foo-4.
+# Start working on level 4 in the undisturbed unversioned folder.
 #
-# No need to add a url here *until* you hit CR and start a new level.
 # If you start a new level before CR,
-# `hg copy` into an n+1 versioned folder,
+# `hg copy` the unversioned folder into an n+1 versioned folder,
 # then unversion it with `hg rename` when level n hits CR.
+# That is, if you start work on Foo level 4 before Foo level 3 is done,
+# run `hg copy css-foo css-foo-4` and work on it there.
+# Then, when you're ready for level 4 to be the new baseline dev version
+# (when level 3 is done, in CR, and not receiving major editor attention),
+# run `hg mv css-foo css-foo-3` and `hg mv css-foo-4 css-foo`
+# so that the mainline version is back in an unversioned folder,
+# and update the rule below accordingly.
+#
+# If you start an entirely new spec,
+# just make an unversioned folder
+# and add a rule below redirecting an appropriately versioned url to your folder.
 
 RewriteRule ^css-align-3/(.*)$ css-align/$1
 RewriteRule ^css-animations-1/(.*)$ css-animations/$1