[TIMOB-5212] Files in the project root's Resources/iphone folder cannot be loaded by the iOS simulator

Platform-specific images are placed in the following project directories:

Resources/android/images/high/ic_tab_home.png
Resources/android/images/medium/ic_tab_home.png
Resources/android/images/low/ic_tab_home.png
Resources/iphone/images/ic_tab_home.png
Resources/iphone/images/ic_tab_home@2x.png

These are used to set icons to tabs, in the following working code:

var tabGroup = Ti.UI.createTabGroup();

var win1 = Ti.UI.createWindow({
  title:'Tab 1',
  backgroundColor:'#fff'
});
var tab1 = Ti.UI.createTab({
  icon:"/images/ic_tab_home.png",
  title:'Tab 1',
  top:0,
  left:0,
  right:0,
  bottom:0,
  width:'100%',
  height:'100%',
  window:win1
});

tabGroup.addTab(tab1);

tabGroup.open();

When the iPhone version of builder.py launches the iOS simulator, it does so in a manner causing the app resources to be loaded from the project root folder instead of the app's resource folder in the iphone build folder. This is causing significant issues when loading device specific resources residing in the Resources/iphone folder. For instance, attempting to load the file Resources/iphone/images/KS_nav_ui.png using the path images/KS_nav_ui.png or /images/KS_nav_ui.png no longer works. If you put them in a top level /images folder, they end up overriding their Android density-specific counterparts when the Android version of builder.py runs. It appears builder.py is correctly copying files from the Resources/iphone folder to the app's resource folder residing at build/iphone/build/Debug-iphonesimulator/_appname_.app. For instance, the file Resources/iphone/images/KS_nav_ui.png is correctly copied to build/iphone/build/Debug-iphonesimulator/_appname_.app/images/KS_nav_ui.png. But since the iOS simulator is loading the resources directly from the project root, the files in the app resource folder are ignored. At present... there doesn't appear to be a graceful workaround to this issue without creating a device specific path at runtime and ingesting it into each path reference for device-specific resources, a significant change to any existing codebase of medium or larger size.