v2.7.8 release (#1201)

## _v2.7.8 (20200622)_

**[BREAKING CHANGES]**
- Fix Manchester code handling; Increase Airwell to `34` bits. (#1200)

**[Bug Fixes]**
- Carrier40: Use correct gap value. (#1193)

**[Features]**
- CarrierAc64: Add detailed support. (#1133)
- Add experimental support for Hitachi A/C 344 bit protocol (#1139)
- Automatic & full library code/API documentation via Doxygen (#1150 #1154 #1155 #1156 #1158 #1165 #1167 #1169 #1180 #1184 #1189 #1191 #1194 #1195 #1197 #1198)
- Hitachi344: Add detailed support and change bit ordering. (#1147)
- Add Corona AC Protocol (#1152)
- Hitachi344: Add Swing(H) and improve Swing(V) (#1148)
- Update auto_analyse_raw_data.py with better code comment sections (#1164)
- Add support for Midea24 protocol. (#1171)
- Add basic Zepeal protocol support (#1178)

**[Misc]**
- scrape_supported_devices.py: avoid changes to SupportedProtocols.md (#1140)
- auto_analyze nice exit on empty rawdata input (#1141)
- Comments update + cleanup (#1143)
- Update D_STR_IRRECVDUMP_STARTUP text and comments. (#1144)
- Minor code cleanups (#1149)
- Update `README.md`'s to point to new API docs. (#1151)
- Update "Supports" sections (#1160)
- Add a `doxygen` check to CI/Travis. (#1161)
- scrape_supported_devices: warn about misplaced or legacy supports sections (#1159)
- Add Supports sections to some files (#1163 #1166)
- Fix compile error when `DEBUG` is enabled.
- Add no-output option and return code on error to scrape_supported_devices
- Travis: Add scrape_supported_devices error check
- Update auto_analyse_raw_data.py to have a default Supports: section
- Treat compiler warnings as errors. (#1174)
- Remove `calcLGChecksum()` and use new generic `sumNibbles()` (#1175)
- Suppress more potential compiler warnings. (#1179)
- Load balance travis tasks to reduce wall clock time. (#1183)
- Set PlatformIO's default baudrate to 115200 (#1188)
- Some fixes to Doshisha protocol handler
- Minor cleanups of Corona and Zepeal
- Enable Doxygen warning when the parameters for a function/method/procedure are wrong/missing. (#1196)

library.properties

@@ -1,5 +1,5 @@
 name=IRremoteESP8266
-version=2.7.7
+version=2.7.8
 author=David Conran, Sebastien Warin, Mark Szabo, Ken Shirriff
 maintainer=David Conran, Mark Szabo, Sebastien Warin, Roi Dayan, Massimiliano Pinto, Christian Nilsson
 sentence=Send and receive infrared signals with multiple protocols (ESP8266/ESP32)