restructure (#175)

Part of the clean up was to make all of the db function fail if open had not been called first. Modified dawgie.tools.trace to open and close the db always since the pipeline has correctly closed it already.

Python/dawgie/tools/trace.py

@@ -116,6 +116,7 @@ def main (fn:str=None, at=None):
     images = ''
     routes = {}
     traces = {}
+    dawgie.db.open()
     for root in at: routes.update (_trace (root))
     for key in sorted (routes, key='.'.join):
         algs = set()
@@ -194,6 +195,8 @@ def main (fn:str=None, at=None):
            os.makedirs (os.path.dirname (fn))
         shutil.move (tfn, fn)
     else: webbrowser.open_new_tab ('file://' + tfn)
+
+    dawgie.db.close()
     return
 
 if __name__ == '__main__':
@@ -223,9 +226,7 @@ def main (fn:str=None, at=None):
     args = ap.parse_args()
     dawgie.context.log_level = args.log_level
     dawgie.context.override (args)
-    dawgie.db.open()
     dawgie.tools.trace.main(fn=args.file_name)
-    dawgie.db.close()
 else:
     import dawgie.context
     import dawgie.db