Simplified most traits

[jorgecarleitao]

This PR (finally) separates traits describing physical types from traits describing logical types. This is one of the main requirements I had to address #257 .

With this PR, we may cleanly remove the module types and datatypes into two crates. They contain "core" traits and enums that can live on their own, corresponding to the "physical" and "logical" base representations of this crate.

[codecov]

Codecov Report

Merging #696 (b1186a8) into main (4bbbe62) will increase coverage by 0.05%.
The diff coverage is 44.12%.

@@            Coverage Diff             @@
##             main     #696      +/-   ##
==========================================
+ Coverage   70.44%   70.50%   +0.05%     
==========================================
  Files         300      302       +2     
  Lines       16591    16614      +23     
==========================================
+ Hits        11688    11713      +25     
+ Misses       4903     4901       -2     

Impacted Files	Coverage Δ
src/array/binary/mod.rs	82.14% <ø> (ø)
src/array/list/ffi.rs	65.51% <ø> (ø)
src/array/list/mod.rs	81.39% <ø> (ø)
src/array/mod.rs	67.85% <ø> (ø)
src/array/specification.rs	82.75% <ø> (+4.70%)	⬆️
src/compute/cast/dictionary_to.rs	24.39% <0.00%> (ø)
src/compute/length.rs	100.00% <ø> (ø)
src/compute/sort/mod.rs	26.66% <0.00%> (-0.17%)	⬇️
src/io/csv/read_utils.rs	63.15% <ø> (ø)
src/types/bit_chunk.rs	40.90% <ø> (ø)
... and 29 more

---

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 4bbbe62...b1186a8. Read the comment docs.