Add a fixer command.

editorconfig/check_command.go

@@ -3,7 +3,6 @@ package editorconfig
 import (
 	"fmt"
 	"github.com/codegangsta/cli"
-	"io/ioutil"
 	"strconv"
 	"strings"
 )
@@ -26,11 +25,7 @@ func CheckCommand(c *cli.Context) error {
 			continue
 		}
 
-		fileContentInBytes, err := ioutil.ReadFile(f)
-		if err != nil {
-			ExitBecauseOfInternalError("Could not read file: " + f)
-		}
-		fileContent := string(fileContentInBytes)
+		fileContent := MustGetFileAsString(f)
 
 		// Run full-file checkers.
 		for ruleName, ruleValue := range rules {