munge output type/binary point option

after munging the option is now provided to reinterpret the data
as a specified type and with a specified banry point position. This
is useful if in the input (and required output type) is not Unsigned.
shared bram type/binary point fix

Normally, the Shared BRAM block needs to be used with a binary point
position of 0 and Unsigned data type. Fixes made to support other
arithmetic types and binary point positions.
Merge branch 'master' of github.com:ska-sa/mlib_devel
re-add of new Shared_BRAM block

merge with -s recursive -X theirs caused bad stuff to happen in the shared_BRAM
block. Re-added and library now seems ok.