Update compiler modules for hobart

Standalone driver now builds with the following on CGD machine:

1. nag 6.2
2. intel 18.0.3
3. gnu 8.1.0
4. pgi 18.1

tests/python_for_tests/machines.py

@@ -91,10 +91,10 @@ def machine_specific(mach, supported_compilers, module_names):
     supported_compilers.append('intel')
     supported_compilers.append('gnu')
     supported_compilers.append('pgi')
-    module_names['nag'] = 'compiler/nag/6.1'
-    module_names['intel'] = 'compiler/intel/17.0.4.196'
-    module_names['gnu'] = 'compiler/gnu/4.8.5'
-    module_names['pgi'] = 'compiler/pgi/17.04'
+    module_names['nag'] = 'compiler/nag/6.2'
+    module_names['intel'] = 'compiler/intel/18.0.3'
+    module_names['gnu'] = 'compiler/gnu/8.1.0'
+    module_names['pgi'] = 'compiler/pgi/18.1'
     return
 
   if mach == 'edison':