Updated README with links (and submitted Firefox extension to AMO)

Chrome/README.md

@@ -1,3 +1,3 @@
 # Open In mpv (Chrome)
 
-This code is a copy of [Chrome_Open_In_IINA](https://github.com/iina/iina/tree/develop/browser/Chrome_Open_In_IINA)
+This code is a modified copy of [Chrome_Open_In_IINA](https://github.com/iina/iina/tree/develop/browser/Chrome_Open_In_IINA)

Makefile

@@ -7,10 +7,10 @@ SRCS = src/curl.hpp \
 
 all: release firefox
 
-release:
+release: $(SRCS)
 	$(CXX) $(CXXFLAGS_release) -o open-in-mpv src/main.cpp
 
-debug:
+debug: $(SRCS)
 	$(CXX) $(CXXFLAGS_debug) -o open-in-mpv src/main.cpp
 
 install: release
@@ -30,4 +30,4 @@ clean:
 fmt:
 	clang-format -i src/*.{hpp,cpp}
 
-.PHONY: all release debug install uninstall firefox clean fmt
+.PHONY: all release debug install uninstall firefox clean fmt