Short-date support

[pelletier]

Issue: #63 #231

Implementation of short date and non-timezone-aware date support.

This first implementation uses cloud.google.com/go/civil to represent civil dates. However, turns out importing this package pulls a lot of Google's dependencies, which I don't want to do. civil will need to be extracted and bundled with go-toml.

Todo

• Update date regexp in lexer
• Lex localDate token
• Bundle civil in go-toml without other dependencies
• Marshal support
• Unmarshal support

[codecov]

Codecov Report

Merging #298 into master will increase coverage by 0.34%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #298      +/-   ##
==========================================
+ Coverage   94.21%   94.55%   +0.34%     
==========================================
  Files           9       10       +1     
  Lines        1901     2020     +119     
==========================================
+ Hits         1791     1910     +119     
  Misses         66       66              
  Partials       44       44

Impacted Files	Coverage Δ
token.go	100% <ø> (ø)	⬆️
lexer.go	98.78% <100%> (+0.01%)	⬆️
tomltree_write.go	95.25% <100%> (+0.03%)	⬆️
marshal.go	92.42% <100%> (+0.08%)	⬆️
parser.go	91.79% <100%> (+0.61%)	⬆️
localtime.go	100% <100%> (ø)

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