Use %ZEN.Auxiliary.altJSONSQLProvider for the processing of MDX Drillthrough queries

Consider this code:

```
set SQL="SELECT '5125.72','1714.50'"
do ##class(%ZEN.Auxiliary.jsonSQLProvider).%WriteJSONFromSQL(,SQL)
```
It produces the following output:

```
{
  "children":[
    {
      "HostVar_1":5125.72,
      "HostVar_2":"1714.50"
    }
  ]
}
```
Instead of:
```
{
  "children":[
    {
      "HostVar_1":5125.72,
      "HostVar_2":1714.50
    }
  ]
}
```
This is because `ZENJSISNUM` macro in `%ZEN.Utils.inc` is used to check if a string is a number.
Macro definition is:
```
#define ZENJSISNUM(%val)	($IsValidNum(%val)&&(%val=+(%val))&&(%val <= 9007199254740991)&&(%val >= -9007199254740991))  
```
Note the second condition there: %val=+(%val)

It won't evaluate as true for numbers with `0` at the end, such as `1714.50`, which causes it to be interpreted as a string.

This commit changes to `%ZEN.Auxiliary.altJSONSQLProvider` which does not have this issue.

Fixes #79

Author: eduard93

MDX2JSON/Utils.cls.xml

@@ -168,7 +168,7 @@ Automatic processing of MDX Drillthrough query and outputting resulting listing
 	return:$$$ISERR(st) st
 	
 	set SQL = RS.%GetListingSQL()
-	do ##class(%ZEN.Auxiliary.jsonSQLProvider).%WriteJSONFromSQL(,SQL,,$$$MaxCacheInt)
+	do ##class(%ZEN.Auxiliary.altJSONSQLProvider).%WriteJSONFromSQL(,SQL,,$$$MaxCacheInt)
 
 	return $$$OK
 ]]></Implementation>