ACRA: add more fields to crash reports, but no user identifying info
extended info on things we already have:
- PRODUCT is another name for BRAND/PHONE_MODEL
- TOTAL_MEM_SIZE can be derived from hardware name
- DISPLAY is also available by looking up the hardware
- STACK_TRACE_HASH should make automated sorting easier
new info:
- PACKAGE_NAME is only new info if the user is using a whitelabel app
- AVAILABLE_MEM_SIZE can be used to track users, but only when provided at high resolution, e.g. once per second or higher. Most users only send a single crash report. High frequency reporters send under 100, which is still orders of magnatude below what is needed to track users.