clarify comment in caveats.rst
do not depend on dict serialisation order in doctest
allow fixed size C array declarations in pure mode

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extra : amend_source : 49ba7a5625c69a46f550f471dfbd462a5082b27c
add tips+tricks section to pure mode docs
fix array size check in Shadow module ('float' isn't Python's float)
run expression analysis on function signature annotations (was missing before)

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extra : amend_source : fe959a1a34b1e190fbe051c7058fcf51c50a2fa8