DEJMPS Purification circuit

[sagnikpal2004]

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Closes #237

[codecov]

Codecov Report

Attention: Patch coverage is 6.25000% with 15 lines in your changes missing coverage. Please review.

Project coverage is 64.38%. Comparing base (fea11cc) to head (e519d98).

Files with missing lines	Patch %	Lines
src/CircuitZoo/CircuitZoo.jl	6.25%	15 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #238      +/-   ##
==========================================
- Coverage   72.58%   64.38%   -8.20%     
==========================================
  Files          52       52              
  Lines        2006     2016      +10     
==========================================
- Hits         1456     1298     -158     
- Misses        550      718     +168     

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[Krastanov]

when quantumsavory is released, bump compat bounds

tests should be added

really neat addition, thank you!

[Krastanov]

let's remove the name "Protocol" to avoid confusion with ProtocolZoo

let's introduce the "per-node" parts of the circuits so that they are easy to use from a network simulation

[Krastanov]

add tests of the form

good_bell_pair
noisy_state = f * good_bell_pair + (...) * the_others + ...
slots = Register(4)
res = circuit(slots[1], ...)
if success
      f_out = observable(slots, projector(good_bell_pair))
     @test approx(f_out, theoretical_expression_based_on_f)
end

[Krastanov]

implement this in terms of calling the half-circuits you have already defined below