settings: Include analytics in default distribution.

This moves the analytics module from being a default-off module that
is somewhat difficult to install to being a default part of the
Zulip distribution (both tarballs and what is enabled by default).

.gitattributes

@@ -10,14 +10,12 @@
 *.tif binary
 .gitignore export-ignore
 .gitattributes export-ignore
-/analytics export-ignore
 /static/assets export-ignore
 /bots export-ignore
 /corporate export-ignore
 /static export-ignore
 /tools export-ignore
 /zilencer export-ignore
-/templates/analytics export-ignore
 /templates/corporate export-ignore
 /templates/zilencer export-ignore
 /puppet/zulip_internal export-ignore

zproject/settings.py

@@ -177,7 +177,10 @@ DEFAULT_SETTINGS = {'TWITTER_CONSUMER_KEY': '',
                     'DBX_APNS_CERT_FILE': None,
                     'DBX_APNS_KEY_FILE': None,
                     'PERSONAL_ZMIRROR_SERVER': None,
-                    'EXTRA_INSTALLED_APPS': [],
+                    # Structurally, we will probably eventually merge
+                    # analytics into part of the main server, rather
+                    # than a separate app.
+                    'EXTRA_INSTALLED_APPS': ['analytics'],
                     'DEFAULT_NEW_REALM_STREAMS': {
                         "social": {"description": "For socializing", "invite_only": False},
                         "general": {"description": "For general stuff", "invite_only": False},