Add generic overloads for TryResolveNamed and TryResolveKeyed

[v0idzz]

This adds generic counterparts for TryResolveNamed and TryResolveKeyed extensions.

Closes #1263

[codecov]

Codecov Report

Merging #1287 (420b70b) into develop (6c6c7c0) will decrease coverage by 0.05%.
The diff coverage is 71.42%.

@@             Coverage Diff             @@
##           develop    #1287      +/-   ##
===========================================
- Coverage    76.64%   76.58%   -0.06%     
===========================================
  Files          188      188              
  Lines         5163     5177      +14     
  Branches      1057     1061       +4     
===========================================
+ Hits          3957     3965       +8     
- Misses         708      711       +3     
- Partials       498      501       +3     

Impacted Files	Coverage Δ
src/Autofac/ResolutionExtensions.cs	51.14% <71.42%> (+2.42%)	⬆️
src/Autofac/Util/AsyncReleaseAction.cs	71.42% <0.00%> (-14.29%)	⬇️

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[alistairjevans]

Looks great, thanks!