Petascope_Error from WCPS should contain cause exception when necessary

[Bang Pham Huu]

In Petascope all exceptions for WCPS is inherited from RuntimeException due to the way ANTLR4 processes each tree node and only support throw RuntimeException.

However, the root cause exception was lost (e.g: PetascopeException, SecoreException) while it should be attached to the wrapper exception WCPSException which will have the stack trace to trace easily.

Caused by: petascope.exceptions.WCPSException: Cannot process encode() operator. Reason: Encoding format 'image/jpasdas2' is not supported..
	at petascope.wcps.parser.WcpsEvaluator.visitEncodedCoverageExpressionLabel(WcpsEvaluator.java:333)
	at petascope.wcps.parser.WcpsEvaluator.visitEncodedCoverageExpressionLabel(WcpsEvaluator.java:134)
	at petascope.wcps.parser.wcpsParser$EncodedCoverageExpressionLabelContext.accept(wcpsParser.java:2446)
	at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visitChildren(AbstractParseTreeVisitor.java:68)
	at petascope.wcps.parser.wcpsBaseVisitor.visitProcessingExpression(wcpsBaseVisitor.java:229)
	at petascope.wcps.parser.wcpsParser$ProcessingExpressionContext.accept(wcpsParser.java:542)
	at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:44)
	at petascope.wcps.parser.WcpsEvaluator.visitReturnClauseLabel(WcpsEvaluator.java:303)
	at petascope.wcps.parser.WcpsEvaluator.visitReturnClauseLabel(WcpsEvaluator.java:134)
	at petascope.wcps.parser.wcpsParser$ReturnClauseLabelContext.accept(wcpsParser.java:440)
	at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:44)
	at petascope.wcps.parser.WcpsEvaluator.visitWcpsQueryLabel(WcpsEvaluator.java:267)
	at petascope.wcps.parser.WcpsEvaluator.visitWcpsQueryLabel(WcpsEvaluator.java:134)
	at petascope.wcps.parser.wcpsParser$WcpsQueryLabelContext.accept(wcpsParser.java:153)
	at org.antlr.v4.runtime.tree.AbstractParseTreeVisitor.visit(AbstractParseTreeVisitor.java:44)
	at petascope.wcps.parser.WcpsTranslator.getTranslationTree(WcpsTranslator.java:97)
	... 61 more

****************** Newly added from root cause ******************

Caused by: petascope.exceptions.PetascopeException: Encoding format 'image/jpasdas2' is not supported.
	at petascope.util.MIMEUtil.getMimeType(MIMEUtil.java:206)
	at petascope.wcps.handler.EncodeCoverageHandler.handle(EncodeCoverageHandler.java:80)
	at petascope.wcps.parser.WcpsEvaluator.visitEncodedCoverageExpressionLabel(WcpsEvaluator.java:330)