Adding file doc fragment to those modules in files/ missing it

lib/ansible/modules/files/ini_file.py

@@ -23,6 +23,7 @@ DOCUMENTATION = '''
 ---
 module: ini_file
 short_description: Tweak settings in INI files
+extends_documentation_fragment: files
 description:
      - Manage (add, remove, change) individual settings in an INI-style file without having
        to manage the file as a whole with, say, M(template) or M(assemble). Adds missing

lib/ansible/modules/files/lineinfile.py

@@ -28,6 +28,7 @@ DOCUMENTATION = """
 ---
 module: lineinfile
 author: Daniel Hokka Zakrisson, Ahti Kitsik
+extends_documentation_fragment: files
 short_description: Ensure a particular line is in a file, or replace an
                    existing line using a back-referenced regular expression.
 description:

lib/ansible/modules/files/replace.py

@@ -26,6 +26,7 @@ DOCUMENTATION = """
 ---
 module: replace
 author: Evan Kaufman
+extends_documentation_fragment: files
 short_description: Replace all instances of a particular string in a
                    file using a back-referenced regular expression.
 description:

lib/ansible/modules/files/unarchive.py

@@ -24,6 +24,7 @@ DOCUMENTATION = '''
 module: unarchive
 version_added: 1.4
 short_description: Copies an archive to a remote location and unpack it
+extends_documentation_fragment: files
 description:
      - The M(unarchive) module copies an archive file from the local machine to a remote and unpacks it.
 options: