Add arrow-ipc Array -> Byes codec

codecs/arrow-ipc/README.md

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+# Arrow IPC Codec
+
+Defines and `array -> bytes` that serializes arrays into the [Arrow IPC format](https://arrow.apache.org/docs/format/IPC.html).
+This codec can be used in place of the standard `Bytes` codec with any data type which can be safely interpreted as an [Arrow Data Type](https://arrow.apache.org/docs/python/api/datatypes.html).
+
+## Codec name
+
+The value of the `name` member in the codec object MUST be `arrow-ipc`.
+
+## Configuration parameters
+
+- `column_name`: the name of column used for generating an Arrow record batch from the Zarr array data. Implementations SHOULD use the name of the Zarr array here.
+
+## Example
+
+```json
+{
+    "codecs": [{
+        "name": "arrow-ipc",
+        "configuration": {"column_name": "temperature"}
+    }],
+}
+```
+
+## Format and algorithm
+
+This is a `array -> bytes` codec.
+
+The codec encodes each Zarr chunk as a standalone Arrow IPC Stream containing a single Record Batch with a single Column.
+
+The encoding process is as follows. For each chunk input array:
+
+1. Flatten the array to a 1D array using C ordering.
+1. Interpret the 1D array as an Arrow Array.
+1. Wrap the Arrow Array in an Arrow Table with a single column, using the `column_name` configuration parameter to define the name of the column.
+1. Write the Arrow Table to an in-memory buffer as an Arrow IPC Stream.
+
+For the decoding process, this is reversed:
+1. Read a the bytes as an Arrow IPC Stream, reading only a single Record Batch.
+1. Extract the Arrow Array column identified by `column_name`.
+1. Interpret this 1D Arrow Array as a slice of a Zarr Array using an appropriate Zarr Data Type.
+1. Reshape the array according to the chunk shape assuming C ordering of the items.
+
+## Change log
+
+No changes yet.
+
+## Current maintainers
+
+* [Ryan Abernathey](https://github.com/rabernat)