Work towards Batcher unification (#553)

* Generalize batchers for all containers

* Document and organize MergeBatcher

* Make generic versions canonical

* Implement account for columnation MergerChunk

* Update colunmar example

* Correct greivous bug in merging

* Update columnar exchange function

* Update src/trace/implementations/merge_batcher.rs

Co-authored-by: Petros Angelatos <[email protected]>

* Remove merge_batcher_col.rs

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Co-authored-by: Petros Angelatos <[email protected]>

Author: frankmcsherry

Cargo.toml

@@ -39,11 +39,13 @@ byteorder="1"
 itertools="^0.13"
 serde_json = "1.0"
 graph_map = "0.1"
+bytemuck = "1.18.0"
 
 [dependencies]
 serde = { version = "1.0", features = ["derive"] }
 fnv="1.0.2"
 timely = {workspace = true}
+columnar = "0.2"
 
 [workspace.dependencies]
 timely = { version = "0.15", default-features = false }