Rename fileExists to exists to match nodejs File System native interface

lib/smb2.js

@@ -356,7 +356,7 @@ proto.writeFile = function(src, dest, cb){
     checkDone();
   }
 
-  this.fileExists(dest, function(err, exists){
+  this.exists(dest, function(err, exists){
 
     if(err) cb && cb(err);
 
@@ -384,8 +384,8 @@ proto.writeFile = function(src, dest, cb){
 
 
 /*
- * fileExists
- * =========
+ * exists
+ * ======
  *
  * test the existence of a file
  *
@@ -394,7 +394,7 @@ proto.writeFile = function(src, dest, cb){
  *  - close the file
  *
  */
-proto.fileExists = function(path, cb){
+proto.exists = function(path, cb){
 
   var connection = this;
 
@@ -424,7 +424,7 @@ proto.fileExists = function(path, cb){
 proto.unlinkFile = function(path, cb){
   var connection = this;
 
-  this.fileExists(path, function(err, exists){
+  this.exists(path, function(err, exists){
 
     if(err) cb && cb(err);