Moving script files to specific folder and change function name of cStringCopy

[bernardinus]

• move Appsflyer script files to Appsflyer folder
  Move Appsflyer cs script path to Appsflyer folder in Assets, because we can't to call our class in AppsflyerTrackerCallback.cs.
  We need to move AppsflyerTrackerCallback.cs outside of Plugins folder by ourselves because it exists in Plugins folder and always compiled in the first phase.
  Reference : https://docs.unity3d.com/Manual/ScriptCompileOrderFolders.html

• change cStringCopy to cAFStringCopy [iOS]
  If there is a function with the same name will get EXC_BAD_ACCESS if executed in iOS, because only used internally better change the function name to reduce conflict.

[stopiccot]

+1 for moving appsflyer sdk to a specific folder

[Deathwing]

Moving the SDK to a separate folder is must-have...don't know why the SDK on its own doesn't support that yet.