Expose Sass lang version via node-sass API and CLI

API Usage:

```javascript
var sass = require('node-sass')
console.log(sass.info)

/*
node-sass       3.7.0   (Wrapper)       [JavaScript]
libsass         3.3.6   (Sass Compiler) [C/C++]
Sass            3.4     (Sass Language) [Sass]
*/
```

CLI Usasge:

```sh
node-sass -v

node-sass       3.7.0   (Wrapper)       [JavaScript]
libsass         3.3.6   (Sass Compiler) [C/C++]
Sass            3.4     (Sass Language) [Sass]
```

lib/extensions.js

@@ -278,7 +278,8 @@ function hasBinary(binaryPath) {
 function getVersionInfo(binding) {
   return [
     ['node-sass', pkg.version, '(Wrapper)', '[JavaScript]'].join('\t'),
-    ['libsass  ', binding.libsassVersion(), '(Sass Compiler)', '[C/C++]'].join('\t'),
+    ['LibSass  ', binding.libsassVersion(), '(Sass Compiler)', '[C/C++]'].join('\t'),
+    ['Sass     ', binding.languageVersion(), '(Sass Language)', '[Sass]'].join('\t')
   ].join(eol);
 }
 

src/binding.cpp

@@ -331,12 +331,17 @@ NAN_METHOD(libsass_version) {
   info.GetReturnValue().Set(Nan::New<v8::String>(libsass_version()).ToLocalChecked());
 }
 
+NAN_METHOD(libsass_language_version) {
+  info.GetReturnValue().Set(Nan::New<v8::String>(libsass_language_version()).ToLocalChecked());
+}
+
 NAN_MODULE_INIT(RegisterModule) {
   Nan::SetMethod(target, "render", render);
   Nan::SetMethod(target, "renderSync", render_sync);
   Nan::SetMethod(target, "renderFile", render_file);
   Nan::SetMethod(target, "renderFileSync", render_file_sync);
   Nan::SetMethod(target, "libsassVersion", libsass_version);
+  Nan::SetMethod(target, "languageVersion", libsass_language_version);
   SassTypes::Factory::initExports(target);
 }
 

test/api.js

@@ -1,15 +1,17 @@
 /*eslint new-cap: ["error", {"capIsNewExceptions": ["Color"]}]*/
 
 var assert = require('assert'),
-  fs = require('fs'),
-  path = require('path'),
-  read = fs.readFileSync,
-  sassPath = process.env.NODESASS_COV
-      ? require.resolve('../lib-cov')
-      : require.resolve('../lib'),
-  sass = require(sassPath),
-  fixture = path.join.bind(null, __dirname, 'fixtures'),
-  resolveFixture = path.resolve.bind(null, __dirname, 'fixtures');
+    eol = require('os').EOL,
+    fs = require('fs'),
+    path = require('path'),
+    sass = require(sassPath),
+    sassPath = process.env.NODESASS_COV
+             ? require.resolve('../lib-cov')
+             : require.resolve('../lib');
+
+var fixture = path.join.bind(null, __dirname, 'fixtures'),
+    read = fs.readFileSync,
+    resolveFixture = path.resolve.bind(null, __dirname, 'fixtures');
 
 describe('api', function() {
 
@@ -1829,12 +1831,14 @@ describe('api', function() {
       info = sass.info;
 
     it('should return a correct version info', function(done) {
-      assert(info.indexOf(package.version) > 0);
-      assert(info.indexOf('(Wrapper)') > 0);
+      var lines = info.split(eol);
+
+      assert(info.indexOf('[C/C++]') > 0);
       assert(info.indexOf('[JavaScript]') > 0);
       assert(info.indexOf('[NA]') < 0);
+      assert.equal(lines[0], ['node-sass', package.version, '(Wrapper)', '[JavaScript]'].join('\t'));
       assert(info.indexOf('(Sass Compiler)') > 0);
-      assert(info.indexOf('[C/C++]') > 0);
+      assert(info.indexOf('(Sass Language)') > 0);
 
       done();
     });