update xsns_61_MI_NRF24.ino

[Staars]

Description:

• lots of refactoring (without new functions code size would have been reduced a lot)
• added multi-page web UI
• added simple beacon function
• added command interface

Command Interface:
NRFPAGE x , shows x sensors per page (default 4)

NRFIGNORE x, ignore sensor type x (1 - Flora, ..., 6 - CGD1), x=0 will ignore nothing

NRFSCAN x, scan for BLE-advertisments -> x=0: new scan list, x=1: append to scan list, x=2: stop scan, all will stop a running beacon.
List-example in the console:
15:16:31 MINRF: Beacon 00: AABBCCDDEEFF Cid: 004C Svc: 0000 UUID: 0000
15:16:31 MINRF: Beacon 01: AABBCCDDEEFF Cid: 004C Svc: 0000 UUID: 0000
15:16:31 MINRF: Beacon 02: AABBCCDDEEFF Cid: 004C Svc: 0000 UUID: 0000
(Note: Cid 004c is Apple, so MAC changes every few minutes anyway -> not feasible as "simple" beacon)

NRFBEACON x, x="1-3 digits" use entry from list above, x="12 characters" read as (uppercase!) MAC-String, both will start simple beacon function with support for RULES and mqtt with upcounting value every second. RULE-JSON after 2 seconds: {NRF:{"Beacon": 2}}, will reset with every received packet.

This chip is still no and will never be a real BLE-device, but it can do quite a lot for the price.

Checklist:

• [x ] The pull request is done against the latest dev branch
• [x ] Only relevant files were touched
• [x ] Only one feature/fix was added per PR.
• [x ] The code change is tested and works on core Tasmota_core_stage
• [x ] The code change pass travis tests. Your PR cannot be merged unless tests pass
• [x ] I accept the CLA.