Fix Issue #938: Added the enhancement - fully parsing of CRD

Summary of changes (CRD.java, CRDConfiguration.java, CRDHeader.java, CRDParser.java, and CRDParserTest.java):

1. Two classes are added, NptRangeMeasurement and FrRangeMeasurement, which extend from RangeMeasurement.
2. The configuration records are stored as a Map in the class CRDConfiguration, and the system configuration records are also store in a list, to support 2-color range system.
3. Comment lines can occur anywhere within a file, especially the begining of the file.
4. Handle 'na'. The literal “na” is used instead of “-1” for fields that are not applicable or not avaiable.
5. The configuration records can occur after H2 or H3, not only H4, for the case of many targets and single system configuration.
6. Add a method toCrdString() to all configuration records and data records.
7. Add getH1CrdString(), getH2CrdString(), getH3CrdString(), getH4CrdString(), to the class CRDHeader, so that a crd file can be reproduced.

Added unittest testIssue938() in the class CRDParserTest to check if it is working correctly.