Network traffic mode for status bar [2/3]

* Complete re-write with proper slot in status bar
* Refactor stats calc based on https://github.com/crdroidandroid/android_lineage-sdk/commit/02eddd44ace2cdc32b980ef094808ee5beb63c9b


* Retained optimized code and formatting

Co-authored-by: SpiritCroc <dev@spiritcroc.de>
Co-authored-by: Oliver Scott <olivercscott@gmail.com>
Co-authored-by: Gobinda Joy <gobinda.joy@gmail.com>
Co-authored-by: Hikari-no-Tenshi <kyryljan.serhij@gmail.com>
Change-Id: I8400ff94271d68df9f4ff540134d242b4f201144
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>