* possible fix of 'division by zero' #1345
* fix lang #1348#1346
* fix timestamp `max AC power` #1324
* fix stylesheet overlay `max AC power` #1324
* fix download link #1340
* fix history graph
* try to fix#1331
* fix display of sunrise in `/system` #1308
* fix overflow of `getLossRate` calculation #1318
* improved MqTT by marking sent data and improved `last_success` resends #1319
* added timestamp for `max ac power` as tooltip #1324#1123#1199
* repaired Power-limit acknowledge #1322
* fixed endless loop while switching CMT frequency
* removed obsolete "retries" field from settings #1224
* fixed crash while defining new invertes #1224
* fixed default frequency settings
* added default input power to `400` while adding new inverters
* fixed color of wifi RSSI icon #1224
* moved MqTT info to `system`
* added CMT info for ESP32 devices
* improved CMT settings, now `SCLK` and `SDIO` are configurable #1046, #1150
* changed `Power-Limit` in live-view to `Active Power Control`
* increase length of update file selector #1132
* add option to strip webUI for ESP8266 (reduce code size, add ESP32 special features; `IF_ESP32` directives)
* started to get CMT info into `system` - not finished
* fixed docu #1085
* changed active power limit MqTT messages to QOS2 #1072
* improved alarm messages, added alarm-id to log #1089
* trigger power limit read on next day (if inverter was offline meanwhile)
* disabled improv implementation to check if it is related to 'Schwuppdizitaet'
* changed live view to gray once inverter isn't available
* added inverter status to API
* changed sum of totals on WebGui depending on inverter status #1084
* merge maximum power (AC and DC) from PR #1080
* fix display of hidden SSID checkbox
* changed yield correction data type to `double`, now decimal places are supported
* corrected name of 0.91" display in settings
* attempt to fix MqTT zero values only if setting is there #980, #957
* made AP password configurable #951
* added option to start without time-sync, eg. for AP-only-mode #951
reduced maximum allowed JSON size for API to 6000Bytes #660
small fix: output command at `prepareDevInformCmd` #692
improved inverter handling for MQTT #671
fix blue LED lights up all the time #672
fix installing schedulers if NTP server isn't available
improved zero values on triggers #671
hardcoded MQTT subtopics, because wildcard `#` leads to errors
rephrased some messages on webif, thx to @Argafal#638
added icons to index.html, added wifi-strength symbol on each page
moved packet stats and sun to system.html
refactored communication offset (adjustable in minutes now)