Merge pull request #273 from Bouska/development

Wrong attribut name in qt/worker.py
Revert "[errata] Typo in the spelling of frequency"

This reverts commit 8490ff3a869593f1021942e384a0630c203a91d1.
Merge https://github.com/satanas/Turpial into development
Revert "[errata] Typo in spelling of frequency"

This reverts commit 47fa017b2c03e814638f6d13de1acb54417715b5.