Remove default strip-commands

Default strip-commands have been removed as they are too specific

Recommendation is if you are building in Linux is to use the ones begin used in freedesktop-sdk project (https://gitlab.com/freedesktop-sdk/freedesktop-sdk/blob/freedesktop-sdk-18.08.19/project.conf#L66), for example

Fixes #645 (closed), #304 (closed)