fix get_stacktrace deprecations

===> Compiling _build/default/lib/webmachine/src/webmachine_resource.erl failed
_build/default/lib/webmachine/src/webmachine_resource.erl:205: erlang:get_stacktrace/0: deprecated; use the new try/catch syntax for retrieving the stack backtrace

Signed-off-by: Lincoln Baker <lbaker@chef.io>

Author: lbakerchef

src/webmachine_decision_core.erl

@@ -38,8 +38,8 @@ handle_request(Resource, ReqState) ->
     try
         d(v3b13)
     catch
-        ?STPATTERN(error:_Reason) ->
-            error_response(?STACKTRACE)
+        error:_:Stacktrace ->
+            error_response(Stacktrace)
     end.
 
 wrcall(X) ->

src/webmachine_resource.erl

@@ -210,8 +210,8 @@ resource_call(F, ReqData,
     Result = try
         %% Note: the argument list must match the definition of CALLBACK_ARITY
         apply(R_Mod, F, [ReqData, R_ModState])
-    catch ?STPATTERN(C:R) ->
-            Reason = {C, R, trim_trace(?STACKTRACE)},
+    catch C:R:Stacktrace ->
+            Reason = {C, R, trim_trace(Stacktrace)},
             {{error, Reason}, ReqData, R_ModState}
     end,
     case R_Trace of

test/decision_core_test.erl

@@ -331,8 +331,8 @@ setup() ->
         meck:new(webmachine_resource, MeckOpts),
         Ctx
     catch
-        ?STPATTERN(T:E) ->
-            io:format(user, "~n~p : ~p : ~p", [T, E, ?STACKTRACE]),
+        T:E:Stacktrace ->
+            io:format(user, "~n~p : ~p : ~p", [T, E, Stacktrace]),
             error(setup_failed)
     end.