update usage using flags

README.md

@@ -30,10 +30,10 @@ In order for the `cliverage` tool to run successfully, you need :
 
 Command usage :
 ```bash
-cliverage <path-to-code> <coverage-file> <file-path>
+cliverage -d <code-path> -c <cover-file> [-f <file-path>]
 ```
 
 Arguments :
-- `<path-to-code>` - path to where your code lives
-- `coverage-file` - path to the coverage file
-- `<file-path>` - path to a single file. You can use go package wildcards : `./...` prints every file, `./a/b/...` prints every file located into `./a/b`.
+- `<code-path>` - path to where your code lives
+- `cover-file` - path to the coverage file
+- `-f <file-path>` - path to a single file. You can use go package wildcards : `./...` prints every file, `./a/b/...` prints every file located into `./a/b`.

usage.go

@@ -8,16 +8,16 @@ func usage() {
 	cliverage - print human-readable golang code coverage
 
 %s
-	%s codepath coverfile [filepath]
+	%s -d codepath -c coverfile [-f filepath]
 
 %s
-	codepath
+	-d codepath
 		Path to where lives your code
 
-	coverfile
+	-c coverfile
 		Path to the coverage file generated by "go test -coverprofile".
 
-	filepath
+	-f filepath
 		Optional path to a file (relative to %s).
 
 %s
@@ -26,7 +26,7 @@ func usage() {
 		bold("NAME"),
 		bold("SYNOPSIS"),
 		bold("cliverage"),
-		bold("ARGUMENTS"),
+		bold("OPTIONS"),
 		bold("codepath"),
 		bold("AUTHORS"),
 	)