Added support to write to async writers.

[jorgecarleitao]

This PR adds support to write to AsyncWrite + AsyncSeek (+ Unpin + Send).

The need for AsyncSeek is due to a current limitation of thrift that does not report how many bytes were written in their protocols. This implementation only calls seek of SeekFrom::Current(0) before and after writing to compute how much bytes were written between the calls.

[codecov-commenter]

Codecov Report

Merging #35 (4c9d153) into main (eca414b) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #35      +/-   ##
==========================================
+ Coverage   67.08%   67.10%   +0.01%     
==========================================
  Files          63       63              
  Lines        3482     3481       -1     
==========================================
  Hits         2336     2336              
+ Misses       1146     1145       -1     

Impacted Files	Coverage Δ
src/write/column_chunk.rs	0.00% <ø> (ø)
src/write/dyn_iter.rs	0.00% <ø> (ø)
src/write/file.rs	100.00% <ø> (ø)
src/write/page.rs	0.00% <ø> (ø)
src/write/mod.rs	91.93% <100.00%> (+1.45%)	⬆️

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