Improve c++ for each statements and add mutable for each variant (talonhub#1982)

Co-authored-by: Nicholas Riley <[email protected]>

Author: FireChickenProductivity

core/snippets/snippets/forEachMutableStatement.snippet

@@ -0,0 +1,25 @@
+name: forEachMutableStatement
+phrase: for each mute | each mute
+insertionScope: statement
+---
+
+language: cpp
+-
+for (auto &$1 : $2) {
+    $0
+}
+---
+
+language: java
+-
+for ($1 : $2) {
+    $0
+}
+---
+
+language: javascript | typescript | javascriptreact | typescriptreact
+-
+for ($1 of $2) {
+    $0
+}
+---

core/snippets/snippets/forEachStatement.snippet

@@ -1,11 +1,11 @@
 name: forEachStatement
-phrase: for each
+phrase: for each | each
 insertionScope: statement
 ---
 
 language: cpp
 -
-for ($1 : $2) {
+for (const auto &$1 : $2) {
     $0
 }
 ---