add parameter 'preset' to the custom derive IntoResponse

[ubnt-intrepid]

In the previous method using with = "..", that takes the path to a free function with the same signature as IntoResponse::into_response, it was impossible to properly set the associated type since the information about the specified function is unknown.

This PR introduces a new trait Preset<T> that contains information necessary for code generation, and a parameter 'preset = ".."' to the custom derive IntoResponse to specify the code generation using this trait.

[codecov[bot]]

Codecov Report

Merging #209 into master will increase coverage by 0.3%. The diff coverage is 86.31%.

@@            Coverage Diff            @@
##           master     #209     +/-   ##
=========================================
+ Coverage   57.47%   57.77%   +0.3%     
=========================================
  Files          70       70             
  Lines        6812     6870     +58     
=========================================
+ Hits         3915     3969     +54     
- Misses       2897     2901      +4

Impacted Files	Coverage Δ
tsukuyomi/macros/src/lib.rs	11.11% <ø> (ø)	:arrow_up:
tsukuyomi/tests/integration_tests/macros.rs	72.28% <100%> (+16.51%)	:arrow_up:
tsukuyomi/src/output.rs	47.95% <50%> (-1.52%)	:arrow_down:
tsukuyomi/macros/src/derive_into_response.rs	85% <88.23%> (+1.12%)	:arrow_up:
tsukuyomi-askama/tests/test_askama.rs	91.17% <0%> (+0.26%)	:arrow_up:

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