Specs: Move default layout manager stuff from default styles to getLayoutManager()

sky/specs/modules.md

 Sky Module System
 =================
 
 This document describes the Sky module system.
 
 Overview
 --------
 
 The Sky module system is based on the ``import`` element. In its
 most basic form, you import a module as follows:
@@ skipping 11 matching lines @@
 registered, the parser waits until the list of outstanding
 dependencies is empty. After the parser has finished parsing, the
 document waits until its list of outstanding dependencies is empty
 before the module it represents is marked complete.
 
 
 Module API
 ----------
 
 Within a script in a module, the ``module`` identifier is bound to
-the [``Module`` object](apis.md) that represents the module.
+the ``Module`` object that represents the module.
 
 ### Exporting values ###
 
 A module can export a value by assigning the ``exports`` property of
 its ``Module`` object. By default, the ``exports`` property of a
 ``Module`` is an empty Object. Properties can be added to the object,
 or, it can be set to an entirely different object; for example, it
-could be set to the module's Document itself, in case the point of the
-module is to expose some ``template`` elements.
+could be set to the module's ``Document`` itself, in case the point of
+the module is to expose some ``template`` elements.
 
 ### Exporting element definitions ###
 
 When importing a module into another, Sky looks at the properties on
 the imported module's ``exports`` value, and for each property that is
 an element constructor (generated by ``registerElement()``), it adds
 an element to the importee's element registry.
 
 ### IDL ###
 
@@ skipping 61 matching lines @@
 Where ``name_1`` through ``name_n`` are the names bound to the
 various named imports in the script element's document,
 ``source_code`` is the text content of the script element,
 ``source_module`` is the ``Module`` object of the script element's
 module, and ``value_1`` through ``value_n`` are the values
 exported by the various named imports in the script element's
 document.
 
 When an import fails to load, the ``as`` name for the import gets
 bound to ``undefined``.