* load layers in parallel threads when opening project
* parallel loading by default and settingsin advanced settings
* fix freezing when no layer supports parallel loading
* clean leftover
* fix unwanted remove and typo
* typo
* fix flake8
* load OGR metadata under global mutex
* Revert "load OGR metadata under global mutex"
This reverts commit adcaf9e66ca432ee35143c45af2b383108770a63.
* remove parallel loading capability for OGR
* start application in server test
* import start_app
* fix flake8