Start having useful defaults for SQL

Mostly this means: Havintg a config_spec.ini that has a
local (relative to mediagoblin.ini) sqlite db with the name
"mediagoblin.db".

Also:
- Add to .gitignore
- Add a notice to mediagoblin.ini about the db

.gitignore

@@ -15,6 +15,7 @@
 /user_dev/
 /paste_local.ini
 /mediagoblin_local.ini
+/mediagoblin.db
 /server-log.txt
 
 # Tests

mediagoblin.ini

@@ -5,6 +5,10 @@
 direct_remote_path = /mgoblin_static/
 email_sender_address = "notice@mediagoblin.example.org"
 
+## Uncomment and change to your DB's appropiate setting.
+## Default is a local sqlite db "mediagoblin.db".
+# sql_engine = postgresql:///gmg
+
 # set to false to enable sending notices
 email_debug_mode = true
 

mediagoblin/config_spec.ini

@@ -9,6 +9,7 @@ media_types = string_list(default=list("mediagoblin.media_types.image"))
 db_host = string()
 db_name = string(default="mediagoblin")
 db_port = integer()
+sql_engine = string(default="sqlite:///%(here)s/mediagoblin.db")
 
 # Where temporary files used in processing and etc are kept
 workbench_path = string(default="%(here)s/user_dev/media/workbench")

mediagoblin/db/sql/convert.py

@@ -148,8 +148,7 @@ def convert_media_comments(mk_db):
 def main():
     global_config, app_config = setup_global_and_app_config("mediagoblin.ini")
 
-    sql_conn, sql_db = sql_connect({'sql_engine': 'sqlite:///mediagoblin.db'})
-
+    sql_conn, sql_db = sql_connect(app_config)
     mk_conn, mk_db = mongo_connect(app_config)
 
     Base.metadata.create_all(sql_db.engine)