Add support for Objective C++ (#481)

Add definition for Objective C++ files for uncrustify, clang-format and astyle

README.md

@@ -426,6 +426,10 @@ that caused Neoformat to be invoked.
   - [`uncrustify`](http://uncrustify.sourceforge.net),
     [`clang-format`](http://clang.llvm.org/docs/ClangFormat.html),
     [`astyle`](http://astyle.sourceforge.net)
+- Objective-C++
+  - [`uncrustify`](http://uncrustify.sourceforge.net),
+    [`clang-format`](http://clang.llvm.org/docs/ClangFormat.html),
+    [`astyle`](http://astyle.sourceforge.net)
 - OCaml
   - [`ocp-indent`](http://www.typerex.org/ocp-indent.html),
     [`ocamlformat`](https://github.com/ocaml-ppx/ocamlformat),

autoload/neoformat/formatters/objcpp.vim

@@ -0,0 +1,20 @@
+function! neoformat#formatters#objcpp#enabled() abort
+    return ['uncrustify', 'clangformat', 'astyle']
+endfunction
+
+function! neoformat#formatters#objcpp#uncrustify() abort
+    return {
+        \ 'exe': 'uncrustify',
+        \ 'args': ['-q', '-l OC+'],
+        \ 'stdin': 1,
+        \ }
+endfunction
+
+function! neoformat#formatters#objcpp#clangformat() abort
+    return neoformat#formatters#c#clangformat()
+endfunction
+
+function! neoformat#formatters#objcpp#astyle() abort
+    return neoformat#formatters#c#astyle()
+endfunction
+

doc/neoformat.txt

@@ -392,6 +392,10 @@ SUPPORTED FILETYPES				*neoformat-supported-filetypes*
   - [`uncrustify`](http://uncrustify.sourceforge.net),
     [`clang-format`](http://clang.llvm.org/docs/ClangFormat.html),
     [`astyle`](http://astyle.sourceforge.net)
+- Objective-C++
+  - [`uncrustify`](http://uncrustify.sourceforge.net),
+    [`clang-format`](http://clang.llvm.org/docs/ClangFormat.html),
+    [`astyle`](http://astyle.sourceforge.net)
 - OCaml
   - [`ocp-indent`](http://www.typerex.org/ocp-indent.html),
     [`ocamlformat`](https://github.com/ocaml-ppx/ocamlformat),