Add support for 'mtree' output format in output functions

Author: nmaguiar

src/include/outputFns.js

@@ -68,6 +68,10 @@ var _outputFns = new Map([
     ["tree", (r, options) => {
         _o$o(r, options)
     }],
+    ["mtree", (r, options) => {
+        if (typeof __flags.TREE.mono == "undefined") options.__format = "ctree"
+        _o$o(r, options)
+    }],
     ["res", (r, options) => {
         _o$o(r, options)
     }],

src/include/utilFns.js

@@ -120,7 +120,7 @@ const _$o = (r, options, lineByLine) => {
     if (isDef(params.outkey))    r = $$({}).set(params.outkey, r)
 
     _clearTmpMsg()
-    if (isUnDef(nOptions.__format)) nOptions.__format = getEnvsDef("OAFP_OUTPUT", nOptions.__format, "tree")
+    if (isUnDef(nOptions.__format)) nOptions.__format = getEnvsDef("OAFP_OUTPUT", nOptions.__format, "mtree")
     if (_outputFns.has(nOptions.__format)) {
         _outputFns.get(nOptions.__format)(r, nOptions)
     } else {