Add support for Simapro external links feature
In Simapro developer edition it is possible to link an amount field to an excel spreadsheet cell or a database. This is then exported as the path to the file, surrounded by single quotes on the amount field. For now ELDAM tries to interpret this as a formula and crashes. This should not be too difficult to handle. https://support.simapro.com/articles/Video/Linking-Data-to-Excel