add missing types and conversion functions to cadence package

[dsainati1]

Closes #1219

Description

These types were previously missing from the cadence package, but had equivalents in sema and interpreter. This fills in the missing types and adds encoding, decoding, import and export converters for them.

---

• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[turbolent]

Looks good! Could you please also add tests?

[dsainati1]

Could you please also add tests?

I added tests to encoding_test and convertValues_test; is there something missing that I should also add?

[codecov-commenter]

Codecov Report

Merging #1224 (206c4ed) into master (4348c5d) will decrease coverage by 0.05%.
The diff coverage is 46.66%.

@@            Coverage Diff             @@
##           master    #1224      +/-   ##
==========================================
- Coverage   77.46%   77.40%   -0.06%     
==========================================
  Files         273      273              
  Lines       34764    34821      +57     
==========================================
+ Hits        26929    26953      +24     
- Misses       6760     6793      +33     
  Partials     1075     1075              

Flag	Coverage Δ
unittests	77.40% <46.66%> (-0.06%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
encoding/json/decode.go	71.12% <17.64%> (-2.07%)	⬇️
runtime/convertTypes.go	76.54% <47.05%> (-2.61%)	⬇️
encoding/json/encode.go	93.42% <100.00%> (ø)
types.go	76.92% <100.00%> (+1.51%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 4348c5d...206c4ed. Read the comment docs.

[turbolent]

I added tests to encoding_test and convertValues_test; is there something missing that I should also add?

Ah, I see, looks good! I had missed those, they didn't look like tests right away

[turbolent]

Thank you for cleaning this up!