Refactor

[dbrattli]

• Protect map and bind from exceptions
• Add protect handler that can be used in pipelines to protect from exceptions
• Fix builder For-method
• Rename throw to fail (since errors goes down)
• Add builder Yield method

[codecov[bot]]

Codecov Report

Merging #84 (8ee8c7e) into master (bbaa2ea) will decrease coverage by 1.04%. The diff coverage is 66.15%.

@@            Coverage Diff             @@
##           master      #84      +/-   ##
==========================================
- Coverage   77.59%   76.55%   -1.05%     
==========================================
  Files           9        9              
  Lines         732      789      +57     
  Branches       13       13              
==========================================
+ Hits          568      604      +36     
- Misses        157      178      +21     
  Partials        7        7              

Impacted Files	Coverage Δ
src/Middleware/Builder.fs	0.00% <0.00%> (ø)
src/Middleware/Error.fs	77.31% <62.50%> (-10.62%)	:arrow_down:
src/Middleware/Core.fs	78.44% <73.33%> (-1.05%)	:arrow_down:
src/HttpHandler/HttpHandler.fs	75.49% <83.33%> (-0.14%)	:arrow_down:
src/HttpHandler/Builder.fs	100.00% <100.00%> (+11.11%)	:arrow_up: