get: language feedback on --show-url PR

per https://github.com/iterative/dvc/pull/3156#pullrequestreview-345562608

dvc/api.py

@@ -47,11 +47,11 @@ class UrlNotDvcRepoError(DvcException):
     """Thrown if given url is not a DVC repository.
 
     Args:
-        url (str): url to the repository.
+        url (str): URL to the repository
     """
 
     def __init__(self, url):
-        super().__init__("URL '{}' is not a dvc repository.".format(url))
+        super().__init__("URL '{}' is not a DVC repository.".format(url))
 
 
 def get_url(path, repo=None, rev=None, remote=None):

dvc/command/get.py

@@ -19,7 +19,7 @@ class CmdGet(CmdBaseNoRepo):
             )
             logger.info(url)
         except DvcException:
-            logger.exception("failed to show url")
+            logger.exception("Failed to show URL")
             return 1
 
         return 0
@@ -78,6 +78,6 @@ def add_parser(subparsers, parent_parser):
     get_parser.add_argument(
         "--show-url",
         action="store_true",
-        help="Returns path/url to the location in remote for specified path",
+        help="Returns URL to the storage location of the target data.",
     )
     get_parser.set_defaults(func=CmdGet)