Correcting typos in docs

lib/main.js

@@ -242,7 +242,7 @@ http.post('http://localhost/post?param1=value1&param2=value2', function (err
 
 // explicit POST request, saves the response body to file
 
-// for Buffer reqBody, the content-lenght header is reqBody.lenght
+// for Buffer reqBody, the content-length header is reqBody.length
 var reqBody = {
 	param1: 'value1',
 	param2: 'value2'
@@ -363,7 +363,7 @@ http.put({
 
 // pipe a HTTP response (a http.IncomingMessage Object) to a PUT request
 // http-request knows how to handle an IncomingMessage
-// content-lenght is taken from the response if exists
+// content-length is taken from the response if exists
 require('http').get('http://example.org/file.ext', function (im) {
 	http.put({
 		url: 'http://localhost/put',
@@ -388,7 +388,7 @@ http.put({
 	url: 'http://localhost/put',
 	reqBody: readableStream,
 	headers: {
-		'content-lenght': 1337,
+		'content-length': 1337,
 		'content-type': 'text/plain'
 	}
 }, 'put.bin', function (err, res) {

lib/request.js

@@ -763,7 +763,7 @@ module.exports = Request;
  * @property {Boolean} noSslValidation Optional; turns of the SSL validation. **Warning:** do this only if you know what you're doing and if you have proper reasons for doing it. Making SSL useless is not a small thing to do
  * @property {Boolean} stream Optional; passes a ReadableStream back to the completion callback of a HTTP request
  * @property {Boolean} noRedirect Optional; turns off the HTTP redirects. Passes back the headers and body of the redirect response. Adds a couple of response headers which indicate the redirection target: redirect-to-url - which indicates the target URL for the redirect as the location header might be a relative path, and redirect-to-host if there's a specified host header in the request
- * @property {Buffer|Stream} reqBody Optional; the contents of the request body for PUT, POST, etc. requests. Must be a Buffer or a Readable Stream instance. For Buffers, the content-length is Buffer.lenght. For a Readable Stream you must pass a content-length header, unless you're building a POST request with the [form-data](https://github.com/felixge/node-form-data) module. The library makes no assumptions about the content-type header, unless you're building a form with form-data
+ * @property {Buffer|Stream} reqBody Optional; the contents of the request body for PUT, POST, etc. requests. Must be a Buffer or a Readable Stream instance. For Buffers, the content-length is Buffer.length. For a Readable Stream you must pass a content-length header, unless you're building a POST request with the [form-data](https://github.com/felixge/node-form-data) module. The library makes no assumptions about the content-type header, unless you're building a form with form-data
  * @property {Object} auth Optional; an Object that contains the authentication information. Currently it only implements HTTP Basic Authentication. The HTTP Basic Authentication was already supported by passing the username:password to the URL itself. This option provides a more API-friendly approach and it adds the basics for implementing HTTP Digest Authentication.
  * @property {String} auth.type The authentication type; Supported value: basic
  * @property {String} auth.username The HTTP Authentication username

test/get.test.js

@@ -283,7 +283,7 @@ describe('HTTP GET method tests', function() {
 				assert.isNull(err, 'we have an error');
 
 				assert.strictEqual(res.code, 206, 'we have the proper status code');
-				assert.isDefined(res.headers['content-length'], 'we have a Content-Lenght');
+				assert.isDefined(res.headers['content-length'], 'we have a Content-Length');
 				assert.strictEqual(res.headers['content-range'], '0-5/11', 'we have the proper value for the Content-Range response header');
 				assert.strictEqual(res.headers['x-http-method'], 'GET', 'the method is GET');