deps: Adjust the header comments in lock files to reflect our tools.

requirements/dev_lock.txt

@@ -1,8 +1,11 @@
 #
-# This file is autogenerated by pip-compile
-# To update, run:
+# This file is GENERATED.  Don't edit directly.
 #
-#    pip-compile --output-file requirements/dev_lock.txt requirements/dev.txt
+# To update, edit the non-"lock" files in requirements/*.txt, then:
+#
+#    tools/update-locked-requirements
+#
+# For details, see requirements/README.md .
 #
 git+https://github.com/umairwaheed/fakeldap.git@37bc199e9589c31f4bb5bae1445ad1cd7f84e1ac#egg=fakeldap==0.5.1.0zulip1
 git+https://github.com/python/mypy.git@d96b2cf22216a4ad6aa55a5726ee35a3fa38c637#egg=mypy==0.530-dev

requirements/prod_lock.txt

@@ -1,8 +1,11 @@
 #
-# This file is autogenerated by pip-compile
-# To update, run:
+# This file is GENERATED.  Don't edit directly.
 #
-#    pip-compile --output-file requirements/prod_lock.txt requirements/prod.txt
+# To update, edit the non-"lock" files in requirements/*.txt, then:
+#
+#    tools/update-locked-requirements
+#
+# For details, see requirements/README.md .
 #
 git+https://github.com/rafaelmartins/pyoembed.git@eb9901917c2a44b49e2887c077ead84a722c50dc#egg=pyoembed
 git+https://github.com/umairwaheed/talon.git@7d8bdc4dbcfcc5a73298747293b99fe53da55315#egg=talon==1.2.11

tools/update-locked-requirements

@@ -22,6 +22,22 @@ compile_requirements () {
     # pip-tools bug; future, futures are obsolete in python3
     sed -i '/futures==/d' "$output"
     sed -i '/future==/d' "$output"
+
+    (
+        cat <<EOF
+#
+# This file is GENERATED.  Don't edit directly.
+#
+# To update, edit the non-"lock" files in requirements/*.txt, then:
+#
+#    tools/update-locked-requirements
+#
+# For details, see requirements/README.md .
+#
+EOF
+        # This perl invocation strips the existing block of header comments.
+        perl -0pe 's/\A(^#.*\n)*//m' "$output"
+    ) | sponge "$output"
 }
 
 compile_requirements requirements/prod.txt requirements/prod_lock.txt