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## Environment
windows 10 
**Liquibase Version**:
Liquibase Community 4.0.0 by Datical
 Liquibase at 12:19:55 (version 4.0.0 #19 built at 2020-07-13 19:45+0000)

**Liquibase Extension(s) & Version**: 
postgresql-42.2.16.jar

**Database Vendor & Version**:
PostgreSQL 12.4 (Ubuntu 12.4-1.pgdg18.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0, 64-bit

## Description
I have table with column 
` ichmod bit(12) DEFAULT '111111111111'::"bit"`

`liquibase generateChangeLog`
generate error: 

`Unexpected error running Liquibase: java.lang.RuntimeException: java.lang.RuntimeException: liquibase.exception.UnexpectedLiquibaseException: Unknown boolean value: 111111111111`

## Steps To Reproduce
Create test database with table: 

```
CREATE TABLE public.test
(
    iid serial,
    ichmod bit(12) DEFAULT '111111111111'::"bit",
    CONSTRAINT test_pkey PRIMARY KEY (iid)
)
```

Run

```
 liquibase  --driver=org.postgresql.Driver --classpath=./postgresql-42.2.16.jar --url="jdbc:postgresql:// xxx" --changeLogFile=db.changelog-1.1.xml --username="xxx" --password="xxx"  generateChangeLog
```


} else {
                returnValue = this.getFalseBooleanValue(database);
            }
        } else if (value instanceof DatabaseFunction) {
            return value.toString();
        } else if (value instanceof Boolean) {
            if (((Boolean) value)) {
                returnValue = this.getTrueBooleanValue(database);
            } else {
                returnValue = this.getFalseBooleanValue(database);
            }
        } else {
            throw new UnexpectedLiquibaseException("Cannot convert type "+value.getClass()+" to a boolean value");
        }
        return returnValue;
    }
    protected boolean isNumericBoolean(Database database) {
        if (database instanceof Firebird3Database) {
            return false;
        }
        if (database instanceof DerbyDatabase) {
            return !((DerbyDatabase) database).supportsBooleanDataType();
        } else if (database.getClass().isAssignableFrom(DB2Database.class)) {
			return !((DB2Database) database).supportsBooleanDataType();
    	}
        return (database instanceof Db2zDatabase) || (database instanceof DB2Database) || (database instanceof FirebirdDatabase) || (database instanceof
            MSSQLDatabase) || (database instanceof MySQLDatabase) || (database instanceof OracleDatabase) ||
            (database instanceof SQLiteDatabase) || (database instanceof SybaseASADatabase) || (database instanceof
            SybaseDatabase);
    }