Update handling of exceptions in unary_unary interceptors (#27)

* Separate google-api-core and grpcio deps in order to pin grpcio
* Update flow of ExceptionInterceptor.intercept_unary_unary method to
put logic preceding the try/catch into an else block.
* Update LoggingInterceptor.intercept_unary_unary to more safely parse information from response/exception objects.

Author: BenRKarl

ChangeLog

@@ -1,5 +1,8 @@
 * 0.7.0:
 - Google Ads v0_7 release.
+- Address inconsistent exception handling in Exception and Logging
+interceptors.
+- Pin `google-api-core` and `grpcio` dependencies.
 
 * 0.6.0:
 - Add configurable logging functionality.

google/ads/google_ads/__init__.py

@@ -19,4 +19,5 @@
 import google.ads.google_ads.client
 import google.ads.google_ads.errors
 
+
 VERSION = '0.7.0'