setup: add missing hgext.fsmonitor

Before this patch, fsmonitor was not installed along with other extensions. It
did correctly build the C files needed but forgot to copy over the python
files. This patch fixes it by adding fsmonitor and fsmonitor.pywatchman to the
correct install variable.

setup.py

@@ -505,8 +505,9 b" cmdclass = {'build': hgbuild,"
 
 packages = ['mercurial', 'mercurial.hgweb', 'mercurial.httpclient',
             'mercurial.pure',
-            'hgext', 'hgext.convert', 'hgext.highlight', 'hgext.largefiles',
-            'hgext.zeroconf', 'hgext3rd']
+            'hgext', 'hgext.convert', 'hgext.fsmonitor',
+            'hgext.fsmonitor.pywatchman', 'hgext.highlight',
+            'hgext.largefiles', 'hgext.zeroconf', 'hgext3rd']
 
 common_depends = ['mercurial/util.h']