v1.2.0 update

What's Changed

• fix building with 'PZEM004_NO_SWSERIAL' under esp8266 by @vortigont in #79
• Links page by @vortigont in #80
• fix typo at readme by @kaconk17 in #96
• Update README.md by @bembenk18 in #115

New Contributors

• @kaconk17 made their first contribution in #96
• @bembenk18 made their first contribution in #115

Full Changelog: v1.1.2...v1.2.0