Security header refresh

[Tbaut]

• closes Shows "Secure" when connected to cellular internet #266

• closes Show only "Not secure" warning if internet connection is detected. Never show "Secure" in the top right corner. #174

• "Secure" will never be shown again, as we can't be sure and it's a strong word.

• update to the new RNCNetinfo api (this removes a deprecation warning)

• get rid of SecurityStore and unstated shared state and consolidate the little logic in one screen

• remove another android permission that seems unneeded by NetInfo

Todo

• Triple check that the removed permission doesn't affect how things work even on an apk. Done, built an apk and it launched and worked without trouble. ✅

[hanwencheng]

Meet weird problem on iOS simulator, the state does not change when user click back.
I also set the breakpoint there and the listener is not called.

Need to be checked on real iOS device, probably is because simulator's problem

[hanwencheng]

ignore it since it is a known issue (edit: with the simulator)

[pmespresso]

LGTM!

[Tbaut]

Real iPhone test successful by @yjkimjunior :)