Added Dart and Flutter snippets.

I collected (and edited) these from Dart-Code (for VSC) and
YASnippet-snippets and wrote some of them myself.

This is the complete collection in here.

If there's gonna be a Dart-Mode in Doom. Also, this needs to be right
next to it.

Author: Davoodeh

dart-mode/aclass

@@ -0,0 +1,8 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: aclass
+# key: acls
+# --
+abstract class ${1:Name} {
+  $0
+}

dart-mode/afun

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: async fun
+# --
+Future<${1:Type}> ${2:Name}($3) async {
+  $0
+}

dart-mode/bltval

@@ -0,0 +1,12 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: built value
+# key: blt
+# group: dart
+# --
+abstract class ${1:Name} implements Built<$1, $1Builder> {
+  factory $1([void Function($1Builder) updates]) = _$$1;
+  $1._();
+
+  $0
+}

dart-mode/class

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: class
+# --
+class ${1:Name} {
+  $0
+}

dart-mode/do

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: do while
+# --
+do {
+  $0
+} while ($1);

dart-mode/elif

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: if else
+# --
+else if ($1) {
+  $0
+}

dart-mode/ext

@@ -0,0 +1,5 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: ext
+# --
+extends ${1:Name}$0

dart-mode/for

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: for
+# --
+for (var i = 0; i < ${1:count}; i++) {
+  $0
+}

dart-mode/fori

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: for-in
+# --
+for (var ${1:item} in ${2:items}) {
+  $0
+}

dart-mode/fun

@@ -0,0 +1,7 @@
+# -*- mode: snippet -*-
+# contributor: M. Yas. Davoodeh
+# name: fun
+# --
+${1:Type} ${2:Name}($3) {
+  $0
+}