Added new Composer Require method

Author: sensorario

README.md

@@ -28,6 +28,11 @@ In this example after every `composer install` I exec a ctags generation
 ```
 This command exec `composer update`.
 
+```vim
+:ComposerRequireFunc
+```
+This command exec `composer require <vendor/repository> <version>`.
+
 ```vim
 :ComposerJSON
 ```

plugin/vim-composer.vim

@@ -25,6 +25,8 @@ endif
 command! -narg=* ComposerRun call s:ComposerRunFunc(<q-args>)
 command! -narg=* ComposerInstall call s:ComposerInstallFunc(<q-args>)
 command! -narg=* ComposerUpdate call s:ComposerUpdateFunc(<q-args>)
+command! -narg=* ComposerRequire call s:ComposerRequireFunc(<q-args>)
+
 command! ComposerGet call s:ComposerGetFunc()
 command! ComposerJSON call s:OpenComposerJSON()
 
@@ -60,6 +62,10 @@ function! s:ComposerUpdateFunc(arg)
     exe s:ComposerRunFunc("update")
 endfunction
 
+function! s:ComposerRequireFunc(repo, version)
+    exe s:ComposerRunFunc("require", repo, version)
+endfunction
+
 function! g:ComposerKnowWhereCurrentFileIs()
     let g:currentWord = expand('<cword>')
     let l:command = "grep " . g:currentWord . " ./vendor/composer -R | awk '{print $6}' | awk -F\\' '{print $2}'"