Fixed Oracle update error - unquoted reserved word

Hi there,
Even if I've added "PASSWORD" reserved word I still have [that error](https://github.com/liquibase/liquibase/pull/154)  - 
>*Caused by: liquibase.exception.DatabaseException: java.sql.SQLSyntaxErrorException: ORA-00904: "PASSWORD": invalid identifier
	at liquibase.snapshot.jvm.ColumnSnapshotGenerator.snapshotObject(ColumnSnapshotGenerator.java:58)
	at liquibase.snapshot.jvm.JdbcSnapshotGenerator.snapshot(JdbcSnapshotGenerator.java:59)
	at liquibase.snapshot.SnapshotGeneratorChain.snapshot(SnapshotGeneratorChain.java:42)
	at liquibase.snapshot.DatabaseSnapshot.include(DatabaseSnapshot.java:75)
	at liquibase.snapshot.DatabaseSnapshot.replaceObject(DatabaseSnapshot.java:144)
	at liquibase.snapshot.DatabaseSnapshot.includeNestedObjects(DatabaseSnapshot.java:107)
	at liquibase.snapshot.DatabaseSnapshot.include(DatabaseSnapshot.java:94)
	at liquibase.snapshot.DatabaseSnapshot.replaceObject(DatabaseSnapshot.java:144)
	at liquibase.snapshot.DatabaseSnapshot.replaceObject(DatabaseSnapshot.java:157)
	at liquibase.snapshot.DatabaseSnapshot.includeNestedObjects(DatabaseSnapshot.java:107)
	at liquibase.snapshot.DatabaseSnapshot.include(DatabaseSnapshot.java:94)
	at liquibase.snapshot.DatabaseSnapshot.replaceObject(DatabaseSnapshot.java:124)
	at liquibase.snapshot.DatabaseSnapshot.includeNestedObjects(DatabaseSnapshot.java:107)
	at liquibase.snapshot.DatabaseSnapshot.include(DatabaseSnapshot.java:94)
	at liquibase.snapshot.SnapshotGeneratorFactory.createSnapshot(SnapshotGeneratorFactory.java:128)
	at liquibase.snapshot.SnapshotGeneratorFactory.createSnapshot(SnapshotGeneratorFactory.java:139)
	at liquibase.snapshot.SnapshotGeneratorFactory.getDatabaseChangeLogTable(SnapshotGeneratorFactory.java:146)
	at liquibase.database.AbstractJdbcDatabase.checkDatabaseChangeLogTable(AbstractJdbcDatabase.java:619)
	... 5 more
Caused by: java.sql.SQLSyntaxErrorException: ORA-00904: "PASSWORD": invalid identifier
	at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:452)
	at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:400)
	at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:884)
	at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:471)
	at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:199)
	at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:535)
	at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:197)
	at oracle.jdbc.driver.T4CStatement.executeForDescribe(T4CStatement.java:1165)
	at oracle.jdbc.driver.OracleStatement.executeMaybeDescribe(OracleStatement.java:1444)
	at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1662)
	at oracle.jdbc.driver.OracleStatement.executeQuery(OracleStatement.java:1958)
	at oracle.jdbc.driver.OracleStatementWrapper.executeQuery(OracleStatementWrapper.java:1695)
	at liquibase.snapshot.jvm.ColumnSnapshotGenerator.readColumn(ColumnSnapshotGenerator.java:137)
	at liquibase.snapshot.jvm.ColumnSnapshotGenerator.snapshotObject(ColumnSnapshotGenerator.java:53)
	... 22 more*

I'll try to explain the reason why I've override that method.
In parent method *quotingStrategy* is always equals *ObjectQuotingStrategy.LEGACY*
#### Parent method: 
```java
    public String escapeObjectName(String objectName, Class<? extends DatabaseObject> objectType) {
        if (objectName == null || quotingStrategy == ObjectQuotingStrategy.LEGACY) {
            return objectName;
        } else if (objectName.contains("-") || startsWithNumeric(objectName) || isReservedWord(objectName)) {
            return quotingStartCharacter + objectName + quotingEndCharacter;
        } else if (quotingStrategy == ObjectQuotingStrategy.QUOTE_ALL_OBJECTS) {
            return quotingStartCharacter + objectName + quotingEndCharacter;
        }
        return objectName;
    }
```
Then it just doesn't try to check reserved words.
I've changed this behaviour in Oracle implementation:
#### Oracle method:
```java
 public String escapeObjectName(String objectName, Class<? extends DatabaseObject> objectType) {
     if (objectName != null) {
         if (objectName.contains("-") || startsWithNumeric(objectName) || isReservedWord(objectName)) {
             return quotingStartCharacter + objectName + quotingEndCharacter;
         } else if (quotingStrategy == ObjectQuotingStrategy.QUOTE_ALL_OBJECTS) {
             return quotingStartCharacter + objectName + quotingEndCharacter;
         }
     }
     return objectName;
 }
```
and this fixed the problem.