Ignoring redundant patcher fields

[krzemin]

This PR introduces support for patches with redundant fields:

case class Foo(a: A, b: B)
case class Patch(b: B, c: C)

// so far it led to compile error: no accessor named c in source type Foo
Foo(...).patchUsing(Bar(...)) 

// now we have an option to ignore redundant fields in patch
Foo(...).using(Bar(...)).ignoreRedundantPatcherFields.patch
// it patches only value of b: B of Foo

It addresses #106 and partially #98

[codecov]

Codecov Report

Merging #130 into master will decrease coverage by 0.25%.
The diff coverage is 97.22%.

@@            Coverage Diff             @@
##           master     #130      +/-   ##
==========================================
- Coverage   96.21%   95.95%   -0.26%     
==========================================
  Files          11       13       +2     
  Lines         475      495      +20     
  Branches       58       68      +10     
==========================================
+ Hits          457      475      +18     
- Misses         18       20       +2

Impacted Files	Coverage Δ
...nd/chimney/internal/macros/TransformerMacros.scala	95.4% <ø> (ø)	⬆️
...alaland/chimney/internal/dsl/TransformerInto.scala	100% <ø> (ø)	⬆️
...d/chimney/internal/dsl/TransformerDefinition.scala	100% <ø> (ø)	⬆️
...o/scalaland/chimney/internal/dsl/PatcherInto.scala	100% <100%> (ø)
...ala/io/scalaland/chimney/internal/PatcherCfg.scala	100% <100%> (ø)
...io/scalaland/chimney/internal/TransformerCfg.scala	100% <100%> (ø)
.../main/scala/io/scalaland/chimney/Transformer.scala	100% <100%> (ø)	⬆️
...mney/src/main/scala/io/scalaland/chimney/dsl.scala	80% <66.66%> (-20%)	⬇️
...laland/chimney/internal/macros/PatcherMacros.scala	90% <90%> (ø)
... and 3 more

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