An incomplete Rust parser for Clickhouse SQL dialect.

Inspired by nom-sql and written using nom.

Status: basic support for CREATE TABLE statement. Engines options parsed as String. Columns parsed as structs with all options (type, codecs, ttl, comment and so on).

```

cargo b --example parse

... Running target/debug/examples/parse

SQL statement: CREATE TABLE default.access ( remote_addr String CODEC(ZSTD(1)), remote_addr_long Int32 ) ENGINE = DISTRIBUTED( 'cluster', '', 'access', rand());

[examples/parse.rs:20] &schema = CreateTable( CreateTableStatement { table: Table { name: "access", alias: None, schema: Some( "default", ), }, fields: [ ColumnSpecification { column: Column { name: "remoteaddr", alias: None, table: Some( "access", ), }, sqltype: String, codec: Some( CodecList( [ ZSTD( Some( 1, ), ), ], ), ), ttl: None, nullable: false, option: None, comment: None, lowcardinality: false, }, ColumnSpecification { column: Column { name: "remoteaddrlong", alias: None, table: Some( "access", ), }, sqltype: Int( B32, ), codec: None, ttl: None, nullable: false, option: None, comment: None, lowcardinality: false, }, ], engine: Distributed( EngineDistributed { clustername: "\'cluster\'", schema: "\'\'", table: "\'access\'", shardingkey: Some( "rand()", ), policyname: None, }, ), }, ) ```