TAJO-22: The package prefix should be org.apache.tajo. (DaeMyung Kang via hyunsik)
Merge branch 'TAJO-22_RC' into SQL_IMPROVE

Conflicts:
	tajo-algebra/src/main/java/org/apache/tajo/algebra/ExprType.java
	tajo-algebra/src/main/java/tajo/algebra/DropTable.java
	tajo-algebra/src/main/java/tajo/algebra/InExpr.java
	tajo-core/tajo-core-backend/src/main/antlr3/org/apache/tajo/engine/parser/SQLLexer.g
	tajo-core/tajo-core-backend/src/main/antlr3/org/apache/tajo/engine/parser/SQLParser.g
	tajo-core/tajo-core-backend/src/main/antlr3/tajo/engine/parser/SQLLexer.g
	tajo-core/tajo-core-backend/src/main/antlr3/tajo/engine/parser/SQLParser.g
	tajo-core/tajo-core-backend/src/main/antlr4/tajo/engine/parser/SQLLexer.g4
	tajo-core/tajo-core-backend/src/main/antlr4/tajo/engine/parser/SQLParser.g4
	tajo-core/tajo-core-backend/src/main/java/org/apache/tajo/engine/parser/QueryAnalyzer.java
	tajo-core/tajo-core-backend/src/test/java/org/apache/tajo/engine/parser/TestSQLParser.java
	tajo-frontend/tajo-frontend-sql/src/main/antlr3/tajo/frontend/sql/SQLLexer.g
	tajo-frontend/tajo-frontend-sql/src/main/antlr3/tajo/frontend/sql/SQLParser.g
	tajo-frontend/tajo-frontend-sql/src/main/java/org/apache/tajo/frontend/sql/QueryBlock.java
	tajo-frontend/tajo-frontend-sql/src/main/java/org/apache/tajo/frontend/sql/SQLAnalyzer.java
	tajo-frontend/tajo-frontend-sql/src/main/java/org/apache/tajo/frontend/sql/SQLParseError.java
	tajo-frontend/tajo-frontend-sql/src/main/java/org/apache/tajo/frontend/sql/SQLSyntaxError.java
	tajo-frontend/tajo-frontend-sql/src/main/java/tajo/frontend/sql/SQLParseError.java
	tajo-frontend/tajo-frontend-sql/src/main/java/tajo/frontend/sql/SQLSyntaxError.java
	tajo-frontend/tajo-frontend-sql/src/test/java/org/apache/tajo/frontend/sql/TestSQLAnalyzer.java
	tajo-frontend/tajo-frontend-sql/src/test/java/org/apache/tajo/frontend/sql/TestSQLParser.java