add support for excludes in input dir

This adds support for `--include` and `--exclude` for directory inputs.

For instance, this is what you would want to use when passing dagger
repository as an input:

```
inputs:
    repository:
        dir:
            path: .
            exclude:
                - '**/node_modules'
                - cmd/dagger/dagger
                - cmd/dagger/dagger-debug
```

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

cmd/dagger/cmd/compute.go

@@ -57,7 +57,7 @@ var computeCmd = &cobra.Command{
 		for _, input := range viper.GetStringSlice("input-dir") {
 			parts := strings.SplitN(input, "=", 2)
 			k, v := parts[0], parts[1]
-			err := st.SetInput(k, state.DirInput(v, []string{}))
+			err := st.SetInput(k, state.DirInput(v, []string{}, []string{}))
 			if err != nil {
 				lg.
 					Fatal().

cmd/dagger/cmd/input/dir.go

@@ -43,11 +43,20 @@ var dirCmd = &cobra.Command{
 			p = "./" + p
 		}
 
-		updateEnvironmentInput(ctx, args[0], state.DirInput(p, []string{}))
+		updateEnvironmentInput(ctx, args[0],
+			state.DirInput(
+				p,
+				viper.GetStringSlice("include"),
+				viper.GetStringSlice("exclude"),
+			),
+		)
 	},
 }
 
 func init() {
+	dirCmd.Flags().StringSlice("include", []string{}, "Include pattern")
+	dirCmd.Flags().StringSlice("exclude", []string{}, "Exclude pattern")
+
 	if err := viper.BindPFlags(dirCmd.Flags()); err != nil {
 		panic(err)
 	}