Fuse compatibility with straxen (support both straxen v2 and v3)

[cfuselli]

After #282 we were not compatible with older strax and straxen.
Now we address changes needed for being compatible with straxen v2.* and v3.*

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• Check if xnt_common_opts exists or just common_opts, choose accordingly
• Only do purge_configs if supported
• Go back to support older strax(en). Now strax = ">=1.6.0" and straxen = ">=2.2.3"

[coveralls]

Pull Request Test Coverage Report for Build 14080406402

Details

• 9 of 11 (81.82%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.03%) to 79.937%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
fuse/context.py	9	11	81.82%

Totals
Change from base Build 13387532307:	-0.03%
Covered Lines:	2538
Relevant Lines:	3175

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💛 - Coveralls