v0.0.188: [Benchmark] Add CLI argument `num_runs`

Previously, the number of runs had to be adjusted by changing the
corresponding global variable in the script.  This can now be done via
CLI argument.  The default is still 5 runs per system, case, and
configuration.

v0.0.187: [Benchmark] Support index field in connectors

Index support added for mutable, DuckDB, and PostgreSQL.  Notably, HyPer
is not yet supported as index support is currently disabled in
`tableauhyperapi`.  The method field is ignored by all databases but
mutable.

v0.0.186: [Benchmark] Add date tables in phys-cost-models

Tables for `DATE`, `DATETIME`, and `DECIMAL(10,2)` were added.

v0.0.185: [WasmV8] Fix `read_result_set()` without projection present.

Do not assume a projection operator to be present in the logical
plan. Instead insist that it is present if a constant occurs which
was omitted in the result set.

v0.0.184: [IR] Fix `QueryGraph`s swap method.

Add missing data members.

v0.0.183: [IR] Fix dumping nested `QueryGraph`s.

Nested queries in SQL require an alias but internally created nested
queries, e.g. due to HAVING, do not have to.

v0.0.182

[Wasm] Add `get_base_address()` helper function

v0.0.181

[WasmDSL] Support `NChar` in `convert()`

v0.0.180: [Schema] Add `is_valid` flag for indexes

We currently do not support automatic updates on indexes.  To ensure
correct query results, inserts on tables will now invalidate all indexes
on that table such that the indexes are no longer used to answer queries.

v0.0.179

[Wasm] Fix #217: Handle duplicated build keys.