Cleanup makefile. Document fetch

Makefile

@@ -23,11 +23,13 @@ verify: test-image
 		--interactive \
 		--volume $(PWD)/:/home/test/sig \
 		local/sig-test /bin/bash -c " \
-		cp -R sig /tmp/sig; \
-		cd /tmp/sig; \
-		./sig fetch --group maintainers 6B61ECD76088748C70590D55E90A401336C8AAA9; \
-		./sig verify --threshold 1 --method=git --group maintainers; \
-		./sig verify --threshold 3 --method=detached --group maintainers; \
+			cp -R sig /tmp/sig; \
+			cd /tmp/sig; \
+			./sig fetch \
+				--group maintainers \
+				6B61ECD76088748C70590D55E90A401336C8AAA9; \
+			./sig verify --threshold 1 --method=git --group maintainers; \
+			./sig verify --threshold 3 --method=detached --group maintainers; \
 		"
 
 .PHONY: test-image

README.md

@@ -58,6 +58,8 @@ The simple GPG signature toolchain for directories or git repos.
   * Add signature to manifest for this directory
 * sig manifest
   * Generate hash manifest for this directory
+* sig fetch [-g,--group=<group>]
+  * Fetch key by fingerprint. Optionally add to group.
 * sig help
   * Show help text.
 * sig version