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
remove unused import
allow signature return type annotations to provide a more specific return object type for def functions
do not depend on dict serialisation order in doctest
extend C interaction docs to show how to cpdef an external C function

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extra : amend_source : d2906987d10e7770ca09dde406219fb0d6a5d38c
slightly update "sharing declarations" section
fix typo
update "external C code" docs
clean up recent incorrect change in Symtab code that validated the property generation for extension type attributes