Avoid conflict between binary location and workspace

Don't try to create the workspace directory on top of the binary, if the
binary happens to be downloaded to the default workspace directory.

cmd/configure.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"fmt"
+	"os"
 	"path"
 	"text/tabwriter"
 
@@ -35,7 +36,14 @@ You can also override certain default settings to suit your preferences.
 			return err
 		}
 		if usrCfg.Workspace == "" {
-			usrCfg.Workspace = path.Join(usrCfg.Home, path.Base(BinaryName))
+			dirName := path.Base(BinaryName)
+			defaultWorkspace := path.Join(usrCfg.Home, dirName)
+			_, err := os.Stat(defaultWorkspace)
+			// Sorry about the double negative.
+			if !os.IsNotExist(err) {
+				defaultWorkspace = fmt.Sprintf("%s-1", defaultWorkspace)
+			}
+			usrCfg.Workspace = defaultWorkspace
 		}
 
 		apiCfg := config.NewEmptyAPIConfig()