added invalid-columns-handling options to prepare command
implemented validColumnFormat and fixColumnFormat methods in PrepareConfiguration class
reset test dataset for integration tests
minor change within PrepareConfiguration class. added comments
refined invalid-columns-handling option.
Merge branch 'master' of github.com:treasure-data/td-import-java into support-invalid-column-header-handling
merged manually
Merge branch 'master' of github.com:treasure-data/td-import-java into support-invalid-column-header-handling
minor changed
Merge branch 'master' of github.com:treasure-data/td-import-java into support-invalid-column-header-handling
fixed bug: actual column names are not passed from json/msgpack record readers to record writer.
deleted unused test method
fixed test method, TestErrorRecordsHandling.java
fixed bug: actual column names are not passed from apache/syslog config to record reader.
fixed test method, TestApacheFileReader, TestJSONRecordReader and TestSyslogFileReader.java
Merge branch 'master' of github.com:treasure-data/td-import-java into support-invalid-column-header-handling
updated pom.xml. deleted maven.treasure-data.com repo declaration because it is no longer used.