[layout] change the source directory layout

doc/makefile

 all: apydoc
 
 apydoc:
-	epydoc -o apidoc --html -v --graph all --no-private --exclude="__pkginfo__" --exclude="setup" -n "Logilab's mtconverter library" ../
+	epydoc -o apidoc --html -v --graph all --no-private --exclude="__pkginfo__" --exclude="setup" -n "Logilab's mtconverter library" ../logilab/mtconverter
 
 clean:
 	rm -rf apidoc

logilab/__init__.py

+__import__('pkg_resources').declare_namespace(__name__)

setup.py

@@ -38,12 +38,17 @@ except ImportError:
     from distutils.command import install_lib
     USE_SETUPTOOLS = 0
 
-sys.modules.pop('__pkginfo__', None)
 # import optional features
-__pkginfo__ = __import__("__pkginfo__")
+__pkginfo__ = __import__("logilab.mtconverter.__pkginfo__").mtconverter.__pkginfo__
+
 # import required features
-from __pkginfo__ import modname, version, license, description, \
-     web, author, author_email
+modname = __pkginfo__.modname
+version = __pkginfo__.version
+license = __pkginfo__.license
+description = __pkginfo__.description
+web = __pkginfo__.web
+author = __pkginfo__.author
+author_email = __pkginfo__.author_email
 
 distname = getattr(__pkginfo__, 'distname', modname)
 scripts = getattr(__pkginfo__, 'scripts', [])
@@ -127,16 +132,10 @@ def install(**kwargs):
     if USE_SETUPTOOLS:
         if '--force-manifest' in sys.argv:
             sys.argv.remove('--force-manifest')
-    if subpackage_of:
-        package = subpackage_of + '.' + modname
-        kwargs['package_dir'] = {package : '.'}
-        packages = [package] + get_packages(os.getcwd(), package)
-        if USE_SETUPTOOLS:
-            kwargs['namespace_packages'] = [subpackage_of]
-    else:
-        kwargs['package_dir'] = {modname : '.'}
-        packages = [modname] + get_packages(os.getcwd(), modname)
-    if USE_SETUPTOOLS and install_requires:
+    package = subpackage_of + '.' + modname
+    packages = get_packages(os.getcwd(), '')
+    if USE_SETUPTOOLS:
+        kwargs['namespace_packages'] = [subpackage_of]
         kwargs['install_requires'] = install_requires
         kwargs['dependency_links'] = dependency_links
     kwargs['packages'] = packages