2020.12.10

There is rc154 for immediate release to fix major defect introduced in rc153.
 
Often it being observed as increased FT8 decoder lag (most likely we have memory corruption in rc153), 
triggered by DT spinbox value change where rc153 can be recovered on second restart of the program.


rc154 changelog:
- patch to increased FT8 decoder lag issue
- avoid storing double type values in settings file to prevent any possible conflict with user regional settings


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