Test for returned Promises reliably

[alxndrsn]

Fixes balderdashy/sails#7068

[alxndrsn]

AppVeyor build is broken on NodeJS version 4. Node 4 hasn't been maintined since 2018, so can this failure be ignored?

[alxndrsn]

An alternative approach might be to replace

        if (options.during.constructor.name === 'AsyncFunction') {                                                                                                           
          if (!seemsToExpectCallback) {                                                                                                                                      
            promiseOrResultMaybe = promiseOrResultMaybe.then(function(resultMaybe){                                                                                          
              didDuringFnAlreadyHalt = true;                                                                                                                                 
              proceed(undefined, resultMaybe);                                                                                                                               
            });//_∏_                                                                                                                                                         
          }//fi                                                                                                                                                               
          promiseOrResultMaybe.catch(function(e){ proceed(e); });//_∏_                                                                                                       
        } else {                                                                                                                                                             
          if (!seemsToExpectCallback) {                                                                                                                                      
            didDuringFnAlreadyHalt = true;                                                                                                                                   
            return proceed(undefined, promiseOrResultMaybe);                                                                                                                 
          }                                                                                                                                                                  
        } 

with

        if (!seemsToExpectCallback) {                                                                                                                                        
          try {                                                                                                                                                              
            const res = await promiseOrResultMaybe;                                                                                                                          
            didDuringFnAlreadyHalt = true;                                                                                                                                   
            return proceed(undefined, res);                                                                                                                                  
          } catch(err) {                                                                                                                                                     
            proceed(err);                                                                                                                                                    
          }                                                                                                                                                                  
        }