Added Support of TextViewLayout

[jingwei-huang1]

• Created the TextViewLayout
• Created the helper to share the text size calculation for both LabelLayout and TextViewLayout
• Added the unit tests to support TextViewLayout
• Updated the label test cases
• Added the playground for TextViewLayout

[jingwei-huang1]

@nicksnyder Thanks for taking time to review my PR. I updated it based on your feedbacks. Could you please take a look at your convenience?

[codecov-io]

Codecov Report

Merging #98 into master will increase coverage by 0.13%. The diff coverage is 94.88%.

@@            Coverage Diff             @@
##           master      #98      +/-   ##
==========================================
+ Coverage   92.33%   92.46%   +0.13%     
==========================================
  Files          53       58       +5     
  Lines        3053     3305     +252     
==========================================
+ Hits         2819     3056     +237     
- Misses        234      249      +15

Impacted Files	Coverage Δ
LayoutKit/Text.swift	100% <100%> (ø)
LayoutKit/Layouts/LabelLayout.swift	100% <100%> (ø)	:arrow_up:
LayoutKit/Layouts/InsetLayout.swift	100% <100%> (ø)	:arrow_up:
LayoutKitTests/TextExtension.swift	100% <100%> (ø)	:arrow_up:
...youtKit/Internal/NSAttributedStringExtension.swift	100% <100%> (ø)
LayoutKit/Internal/CGSizeExtension.swift	100% <100%> (ø)	:arrow_up:
LayoutKit/Internal/TextViewDefaultFont.swift	40% <40%> (ø)
LayoutKit/Layouts/TextViewLayout.swift	88.17% <88.17%> (ø)
LayoutKitTests/TextViewLayoutTests.swift	99.3% <99.3%> (ø)
... and 4 more

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[jingwei-huang1]

Thanks for your reviewing @staguer I will merge this PR on COB 4/4 if there is no further feedback