* add method to fetch block of first vals in columnar
add method to fetch block of first vals in columnar (this is way faster
than single calls for full columns)
add benchmark
fix import warnings
```
test bench_get_block_first_on_full_column ... bench: 56 ns/iter (+/- 26)
test bench_get_block_first_on_full_column_single_calls ... bench: 311 ns/iter (+/- 6)
test bench_get_block_first_on_multi_column ... bench: 378 ns/iter (+/- 15)
test bench_get_block_first_on_multi_column_single_calls ... bench: 546 ns/iter (+/- 13)
test bench_get_block_first_on_optional_column ... bench: 291 ns/iter (+/- 6)
test bench_get_block_first_on_optional_column_single_calls ... bench: 362 ns/iter (+/- 8)
```
* use remainder
* handle ip adresses in term aggregation
Stores IpAdresses during the segment term aggregation via u64 representation
and convert to u128(IpV6Adress) via downcast when converting to intermediate results.
Enable Downcasting on `ColumnValues`
Expose u64 variant for u128 encoded data via `open_u64_lenient` method.
Remove lifetime in VecColumn, to avoid 'static lifetime requirement coming
from downcast trait.
* rename method
Spotted in `range_date_histogram` query in quickwit benchmark:
5% of time copying docs around, which is not needed in the full index case
remove Column to ColumnIndex deref
Introduced asymetric OptionalCodec / SerializableOptionalCodec
Removed cardinality from the columnar sstable.
Added DynamicColumn
Reorganized all files
Change DenseCodec serialization logic.
Renamed methods to rank/select
Moved versioning footer to the columnar level