Deprecate --require-target-macos-version

This flag is redundant and does not mesh well with the MACOSX_DEPLOYMENT_TARGET environment variable.

Changelog.md

@@ -27,6 +27,12 @@ rules on making a good Changelog.
   version to `delocate==0.11.0`.
   [#215](https://github.com/matthew-brett/delocate/pull/215)
 
+### Deprecated
+
+- `--require-target-macos-version` has been deprecated.
+  `MACOSX_DEPLOYMENT_TARGET` should be used instead of this flag.
+  [#219](https://github.com/matthew-brett/delocate/pull/219)
+
 ### Fixed
 
 - Existing libraries causing DelocationError were not shown due to bad string

delocate/cmd/delocate_wheel.py

@@ -2,6 +2,9 @@
 """Copy, relink library dependencies for wheel.
 
 Overwrites the wheel in-place by default.
+
+This script respects the MACOSX_DEPLOYMENT_TARGET environment variable.
+Set MACOSX_DEPLOYMENT_TARGET to verify and target a specific macOS release.
 """
 
 # vim: ft=python
@@ -69,7 +72,8 @@
 parser.add_argument(
     "--require-target-macos-version",
     type=Version,
-    help="Verify if platform tag in wheel name is proper",
+    help="Verify if platform tag in wheel name is proper (deprecated)"
+    "\nConfigure MACOSX_DEPLOYMENT_TARGET instead of using this flag",
     default=None,
 )