Improved make file and documented.

Makefile

@@ -1,17 +1,36 @@
 .PHONY: all
-all: test
+all: test install
+
+ifeq ($(GOPATH),)
+  GOPATH=~/go
+endif
+
+GODEP=$(GOPATH)/src/github.com/golang/dep/cmd/dep
+
+# get dep if necessary
+$(GODEP):
+	go get -u github.com/golang/dep/cmd/dep
+
+# download all dependencies into the vendor dir
+vendor: $(GODEP) Gopkg.toml Gopkg.lock
+	dep ensure
 
 # runs all tests and benchmarks
 .PHONY: bench
-bench:
+bench: vendor
 	go test -bench .
 	cd encryption && go test -bench=.
 
 # runs all tests
 .PHONY: test
-test:
+test: vendor
 	go test ./...
 
+# installs go-hash
+.PHONY: install
+install: vendor
+	go install
+
 # build a smaller executable without symbols and debug info for all supported OSs and ARCHs
 .PHONY: release release-linux release-windows release-darwin
 
@@ -27,3 +46,16 @@ release-darwin:
 	env GOOS=darwin env GOARCH=amd64 go build -ldflags "-s -w" -o releases/go-hash-darwin-amd64
 
 release: test release-linux release-windows release-darwin
+
+# clean build artifacts, i.e. everything that is not source code, including the vendor directory.
+# Does not remove the installed binary.
+.PHONY: clean
+clean:
+	rm -f go-hash
+	rm -rf vendor
+	rm -rf releases
+
+# uninstall the go-hash binary
+.PHONY: uninstall
+uninstall:
+	rm -f $(GOPATH)/bin/go-hash

README.MD

@@ -364,31 +364,34 @@ adapted from PasswordSafe's
 ## Building
 
 The [releases page](https://github.com/renatoathaydes/go-hash/releases) contains executables for several platforms
-but if your platform is not included or you want to build from source, just clone this repository and build it as follows:
+but if your platform is not included or you want to build from source, just clone this repository and build it as explained below.
+
+### Clone this repo
+
+* Using git:
 
 ```
 git clone [email protected]:renatoathaydes/go-hash.git
+cd go-hash
+```
 
-# install dep if you don't have it
-go get -u github.com/golang/dep/cmd/dep
-
-# sync dependencies
-dep ensure
+* Using Go:
 
-# build or install
-go build
+```
+go get -u github.com/renatoathaydes/go-hash
+cd $GOPATH/src/github.com/renatoathaydes/go-hash
 ```
 
-To run the tests:
+### Build using make
+
+The easiest way to build is with make. From the root directory, just run it:
 
 ```
 make
-
-# or
-
-go test ./..
 ```
 
+This will get anything else required to build, then build, install and run the tests.
+
 To run the benchmarks:
 
 ```
@@ -402,3 +405,29 @@ make release
 ```
 
 The local release files go in the `releases` folder.
+
+> To see a list of all targets, in a shell that supports it (most shells), just type `make ` and hit Tab.
+Otherwise, see the [Makefile](Makefile).
+
+### Build with just go
+
+Make is not necessary to build, it's just use for convenience.
+
+If you don't have make or just don't want to use it, here's how to build go-hash without it:
+
+```
+# install dep if you don't have it
+go get -u github.com/golang/dep/cmd/dep
+
+# sync dependencies
+dep ensure
+
+# build or install
+go build
+```
+
+Run tests with:
+
+```
+go test ./...
+```