Replace deprecated failure crate

[ChriFo]

No description provided.

[codecov]

Codecov Report

Merging #44 into master will increase coverage by 3.38%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #44      +/-   ##
==========================================
+ Coverage   94.47%   97.86%   +3.38%     
==========================================
  Files           8       10       +2     
  Lines         960     1032      +72     
==========================================
+ Hits          907     1010     +103     
+ Misses         53       22      -31     

Impacted Files	Coverage Δ
src/logging.rs	96.15% <ø> (+26.92%)	⬆️
src/ctapi/close.rs	100.00% <100.00%> (ø)
src/ctapi/data.rs	99.54% <100.00%> (+0.95%)	⬆️
src/ctapi/init.rs	99.15% <100.00%> (-0.06%)	⬇️
src/ctapi/mod.rs	100.00% <100.00%> (ø)
src/http.rs	98.80% <100.00%> (ø)
src/lib.rs	89.47% <100.00%> (+38.59%)	⬆️
src/settings.rs	95.71% <100.00%> (ø)
src/tests.rs	100.00% <100.00%> (ø)
... and 5 more

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