Mwax updates

[gsleap]

Fixes #13, #59, #60, #61

[codecov]

Codecov Report

Merging #62 (14ed878) into master (db2f797) will increase coverage by 0.01%.
The diff coverage is 96.91%.

@@            Coverage Diff             @@
##           master      #62      +/-   ##
==========================================
+ Coverage   96.49%   96.50%   +0.01%     
==========================================
  Files          36       35       -1     
  Lines       14208    14883     +675     
==========================================
+ Hits        13710    14363     +653     
- Misses        498      520      +22     

Files Changed	Coverage Δ
src/ffi/mod.rs	90.17% <77.19%> (-0.51%)	⬇️
src/voltage_context/mod.rs	94.33% <85.71%> (-0.22%)	⬇️
src/metafits_context/mod.rs	94.40% <96.29%> (+0.81%)	⬆️
src/ffi/test.rs	97.65% <96.95%> (-0.17%)	⬇️
src/correlator_context/test.rs	96.89% <97.91%> (+0.11%)	⬆️
src/voltage_context/test.rs	98.22% <99.24%> (+0.15%)	⬆️
src/correlator_context/mod.rs	98.36% <100.00%> (+0.11%)	⬆️
src/metafits_context/test.rs	99.80% <100.00%> (+0.01%)	⬆️

... and 1 file with indirect coverage changes