Remove Arduino as a language (#3933)

* Remove Arduino as a language

* Move Arduino samples to C++

* Move .ino entry to its correct place

lib/linguist/languages.yml

@@ -279,16 +279,6 @@ Arc:
   tm_scope: none
   ace_mode: text
   language_id: 20
-Arduino:
-  type: programming
-  color: "#bd79d1"
-  extensions:
-  - ".ino"
-  tm_scope: source.c++
-  ace_mode: c_cpp
-  codemirror_mode: clike
-  codemirror_mime_type: text/x-c++src
-  language_id: 21
 AsciiDoc:
   type: prose
   ace_mode: asciidoc
@@ -528,6 +518,7 @@ C++:
   - ".hxx"
   - ".inc"
   - ".inl"
+  - ".ino"
   - ".ipp"
   - ".re"
   - ".tcc"