2003形式のExcelを書き込む場合、セルの取得時に例外が発生する。

[mygreen]

java.lang.NullPointerException
at com.gh.mygreen.xlsmapper.POICellFormatter.getNumericCellValue(POICellFormatter.java:165)
at com.gh.mygreen.xlsmapper.POICellFormatter.format(POICellFormatter.java:55)
at com.gh.mygreen.xlsmapper.POIUtils.getCellContents(POIUtils.java:234)
at com.gh.mygreen.xlsmapper.POIUtils.isEmptyCellContents(POIUtils.java:262)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.HorizontalRecordsProcessor.saveRecords(HorizontalRecordsProcessor.java:574)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.HorizontalRecordsProcessor.saveProcess(HorizontalRecordsProcessor.java:458)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.IterateTablesProcessor.saveMultipleHorizontalTableCell(IterateTablesProcessor.java:388)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.IterateTablesProcessor.saveTables(IterateTablesProcessor.java:313)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.IterateTablesProcessor.saveProcess(IterateTablesProcessor.java:257)
at com.gh.mygreen.xlsmapper.fieldprocessor.processor.IterateTablesProcessor.saveProcess(IterateTablesProcessor.java:1)
at com.gh.mygreen.xlsmapper.FieldAdaptorProxy.saveProcess(FieldAdaptorProxy.java:65)

[mygreen]

#15 でセルのフォーマッタの実装を変えることで対応。
fix v0.4