GH-80 Provide inferred return type from aggregate function output

Add ECLFuncion "returnsSameAsArgumentType" property
Add HPCCColumMetadata default decimalDigits and columchars
HPCCColumMetadata extracts column size, decimaldigits and/or columchars from
incoming ECLType string.
Therefore HPCCColumnMetaData ctor doesn't require valid sqltype
HPCCJDBCUtils TRAILINGNUMERICPATTERN specifies two new groups in order to easily
Implements ResultSetMetaData getPrecision and getScale

extact n_y information



Signed-off-by: Rodrigo Pastrana <Rodrigo.Pastrana@lexisnexis.com>
GH-80 Changes based on code review
Normalize casing in ECLFunction ctor
Added and use final static default values for colum chars, and decimal digs
Create numeric precedence map, and access method
Fixes SQLEXception issues where column index is not displayed in HPCCResultsetmetadata

Signed-off-by: Rodrigo Pastrana <Rodrigo.Pastrana@lexisnexis.com>
Merge pull request #82 from rpastrana/gh-80-aggfn-rettype

GH-80 Provide inferred return type from aggregate function output