Add image_picker library, refs #10046

Reason: before this commit app crashs in release mode,
there are no settings for this app (in ios settings app).

After adding image_picker library and getImage() function in
lib/common.dart (pre caution against AOT compiller dead code
elemenation) after ask permissions for camera usage.

.hgignore

@@ -5,12 +5,13 @@
 .pub/
 .gradle/
 .orig
+
 build/
 gen/
-ios/.generated/
 packages
 pubspec.lock
 .flutter-plugins
+
 android/gradle
 android/gradlew
 android/gradlew.bat
@@ -21,6 +22,8 @@ android/app/gradlew.bat
 android/app/local.properties
 
 android/app/src/main/java/io/flutter/plugins/GeneratedPluginRegistrant.java
+
+ios/.generated/
 ios/Runner/GeneratedPluginRegistrant.h
 ios/Runner/GeneratedPluginRegistrant.m
 ios/Pods/