[process] fix config booleans parsing

Use `_is_affirmative` util.
See commit 0e862f5

checks.d/process.py

@@ -1,10 +1,11 @@
+# 3rd party
+import psutil
+
 # project
 from checks import AgentCheck
+from config import _is_affirmative
 from util import Platform
 
-# 3rd party
-import psutil
-
 
 class ProcessCheck(AgentCheck):
 
@@ -162,9 +163,9 @@ def get_process_metrics(self, pids, cpu_check_interval, ignore_denied_access=Tru
     def check(self, instance):
         name = instance.get('name', None)
         tags = instance.get('tags', [])
-        exact_match = instance.get('exact_match', True)
+        exact_match = _is_affirmative(instance.get('exact_match', True))
         search_string = instance.get('search_string', None)
-        ignore_denied_access = instance.get('ignore_denied_access', True)
+        ignore_denied_access = _is_affirmative(instance.get('ignore_denied_access', True))
         cpu_check_interval = instance.get('cpu_check_interval', 0.1)
 
         if not isinstance(search_string, list):