Upstream released a version of their proprietary library which does not require any modification to the linker script.

- remove .travis.yml
- ./travis_{script,install}.sh -> ./ci_{script,install}.sh
- flush stdout in test script to see logs more promptly
- adjust git config to ignore 'detachedHead' warnings

Specifically, this will break RFM69_SUPPORT on case insensitive
filesystems due to the RFM69.cpp from the RFM69 lib being ignored
when adding ESPurna's rfm69.cpp

trying to fix #2343
*** [.pio\build\$PIOENV\firmware.bin] TypeError
`expected str, bytes or os.PathLike object, not Dir' trying to evaluate `${__get_flash_size(__env__)}'

as it turns out, PIO platform internals (sometimes) did not use the correct ldscript path

As this is no longer an option since PIO 4.4.0
ref.
04694b4126
https://docs.platformio.org/en/latest/core/history.html

*...I have known you for so long
When we ran in circles...*

Add support for BME680 using libalgobsec proprietary algorithms for precise Indoor Air Quality (IAQ) measurement. Unlike traditional CO2 sensors - and good ones are expensive - it measures nearly all VOCs compounds in the air (plus other gases) and compensates those measurements with its built-in temperature and humidity sensors to determine indoor air quality.

Co-authored-by: Max Prokhorov <prokhorov.max@outlook.com>

* [1/2] use #include for single source

* [2/2] use #include for single source

c/p from the InoToCpp converter that uses scons file node path
while we write binary data as utf-8 (and assume it is utf-8!),
we only ever need this in CI and source is always relative.
with luck, this is on the safe side.

- general conversion from .ino modules into a separate .cpp files
- clean-up internal headers, place libraries into .h. guard .cpp with _SUPPORT flags 
- fix some instances of shared variables instead of public methods
- tweak build system to still build a single source file via os environment variable ESPURNA_BUILD_SINGLE_SOURCE

- don't depend on TRAVIS environment variables
- depend on CI flag to add release variables
- chmod +x

* base envs

* CI: speed up release process (since we still want some .bin files)

* fixup! CI: speed up release process (since we still want some .bin files)

* release dry run

* fixup! release dry run

* adjust

* fix .bin name

* it works

* minor cleanup for current git

* use pio suggestion about ldscript, reduce build_flags impact

* fix linker

* parse ${vars} instead of ignoring them

* add filtering and override file (sneak peak into tasmota's pio config)

* don't generate secure client (for now)

* formatting

* codacy

* PIO: remove -ota envs, handle OTA condition in extra script
* Tweak ESPURNA_BOARD variable
* Support git and latest in ota script
* Handle ESPURNA_FLAGS too
* Try to handle env and projenv in pylint
* Add deprecation comment about -ota envs
* regen arduino.h

* utils: use size instead of objdump, include .text1 in .text calculation

* cleanup class attrs, import

* scripts: memanalyzer fixes

- cleanup duplication
- cleanup external dependencies
- properly use subprocess when calling pio, add debug mode
- cleanup argparse usage, use store_true actions instead of counters
- use python3 syntax and python3 shebang by default
- fix some issues with module dependencies

* move to scripts

* use simple return

* quick fix for rfm

* codacy unused import

* formatting

* show defaults

* while at it, rewrite to make pylint happy

* fix unused

* add windows support + note

* utils/version: use git description token as version, add memoization

* pio: move extra scripts to a separate directory

* pio: add -DAPP_REVISION=... as local build flag