Remove Replacer submodule entry. Fixes #444.

.gitmodules

@@ -70,6 +70,3 @@
 [submodule "pelican-open_graph"]
 	path = pelican-open_graph
 	url = https://github.com/whiskyechobravo/pelican-open_graph.git
-[submodule "replacer"]
-	path = replacer
-	url = https://github.com/narusemotoki/replacer

replacer

@@ -1 +0,0 @@
-Subproject commit 7ce49d52ebfa2b5be81bb1ea8a77b57d65d770d9