fix typo

Author: jianglibo

README.md

@@ -9,7 +9,7 @@ convert one tree.
   var tree = new AsciiTree(BytesLine.getArray("hello")).convert();
   assert.equal("└── hello", tree.toString());
   // or use builder helper.
-  var tree = new AsciiTreeBuilder().withString("hello").withEncode("UTF-8").build().convert();
+  var tree = new AsciiTreeBuilder().withContent("hello").withEncode("UTF-8").build().convert();
   assert.equal("└── hello", tree.toString());
 
   tree.toBufferArray();

README_ZH.md

@@ -9,7 +9,7 @@
   var tree = new AsciiTree(BytesLine.getArray("hello")).convert();
   assert.equal("└── hello", tree.toString());
   // or use builder helper.
-  var tree = new AsciiTreeBuilder().withString("hello").withEncode("UTF-8").build().convert();
+  var tree = new AsciiTreeBuilder().withContent("hello").withEncode("UTF-8").build().convert();
   assert.equal("└── hello", tree.toString());
 
   tree.toBufferArray();
@@ -90,7 +90,7 @@ out:
     .pipe(treeStream()) // 将单一行直接传递下去，将树块转换之后传递
     .pipe(unwrapStream()) // 扁平化成Buffer
     .pipe(dst);
-    
+
   //or define a function
   function treepipe(src) {
    return src.pipe(splitterStream()) //to BytesLine

package.json

@@ -1,6 +1,6 @@
 {
   "name": "my-ascii-tree",
-  "version": "1.0.7",
+  "version": "1.0.8",
   "description": "convert indented line block to an ascii directory tree",
   "main": "index.js",
   "scripts": {