Update Makefile and add version flag

Makefile

@@ -1,32 +1,35 @@
-SHELL := /bin/bash
+# Installation paths
+PREFIX ?= /usr/local
+BINDIR ?= $(PREFIX)/bin
+SYSCONFDIR := $(PREFIX)/etc
 
-ifeq ($(PREFIX),)
-    PREFIX := /usr/local
-endif
-ifeq ($(BINDIR),)
-    BINDIR := $(PREFIX)/bin
-endif
-ifeq ($(SYSCONFDIR),)
-    SYSCONFDIR := $(PREFIX)/etc
-endif
-ifeq ($(GO),)
-    GO := $(shell type -a -P go | head -n 1)
-endif
+# Compilers and tools
+GO ?= go
+
+# Build-time variables
+VERSION ?= $(shell git describe --tags --dirty)
 
 build:
 	mkdir -p build
-	cd src; $(GO) build -ldflags "-w -X 'main.systemConfigDir=$(SYSCONFDIR)'" -o ../build/stormfetch stormfetch
+	cd src; $(GO) build -ldflags "-w -X 'main.StormfetchVersion=$(VERSION)' -X 'main.SystemConfigDir=$(SYSCONFDIR)'" -o ../build/stormfetch stormfetch
 
 install: build/stormfetch config/
-	mkdir -p $(DESTDIR)$(BINDIR)
-	mkdir -p $(DESTDIR)$(SYSCONFDIR)/stormfetch/
-	cp build/stormfetch $(DESTDIR)$(BINDIR)/stormfetch
-	cp -r config/. $(DESTDIR)$(SYSCONFDIR)/stormfetch/
+	# Create directoriy
+	install -dm755 $(DESTDIR)$(BINDIR)
+	#  Install binary
+	install -m755 build/stormfetch $(DESTDIR)$(BINDIR)/stormfetch
 
-run: build/stormfetch
-	build/stormfetch
+install-config:
+	# Create directory
+	install -dm755 $(DESTDIR)$(SYSCONFDIR)
+	# Install files
+	cp -r config $(DESTDIR)$(SYSCONFDIR)/stormfetch/
+
+uninstall:
+	-rm -f $(DESTDIR)$(BINDIR)/stormfetch
+	-rm -rf $(DESTDIR)$(SYSCONFDIR)/stormfetch
 
 clean:
 	rm -r build/
 
-.PHONY: build
+.PHONY: build install install-config uninstall clean