Fix coding style problems in gcloud-pubsub-java

Output from the style checker:

Starting audit...
PublisherApiTest.java:19:8: error: Unused import: com.google.api.gax.grpc.ApiCallSettings. Use /google/src/head/depot/google3/tools/java/remove_unused_imports.py to automatically remove unused imports.
PublisherApiTest.java:34: warning: Wrong order for org.junit.After import. Use /google/src/head/depot/google3/tools/java/sort_java_imports.py to automatically sort your imports.
PublisherApiTest.java:112: error: Line is longer than 100 characters (found 109).
SubscriberApi.java:36:8: error: Unused import: com.google.api.gax.grpc.ApiCallSettings. Use /google/src/head/depot/google3/tools/java/remove_unused_imports.py to automatically remove unused imports.
SubscriberApi.java:192: error: Line is longer than 100 characters (found 102).
SubscriberApi.java:509: error: Line is longer than 100 characters (found 101).
SubscriberApi.java:631: error: Line is longer than 100 characters (found 102).
SubscriberSettings.java:225: error: Line is longer than 100 characters (found 101).
SubscriberSettings.java:319:7: warning: Name 'LIST_SUBSCRIPTIONS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
PublisherApi.java:36:8: error: Unused import: com.google.api.gax.grpc.ApiCallSettings. Use /google/src/head/depot/google3/tools/java/remove_unused_imports.py to automatically remove unused imports.
PublisherApi.java:189: error: Line is longer than 100 characters (found 101).
testing/LocalPublisherImpl.java:82: error: Line is longer than 100 characters (found 109).
PublisherSettings.java:289:7: warning: Name 'LIST_TOPICS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
PublisherSettings.java:314:7: warning: Name 'LIST_TOPIC_SUBSCRIPTIONS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
SubscriberApi.java:36:8: error: Unused import: com.google.api.gax.grpc.ApiCallSettings. Use /google/src/head/depot/google3/tools/java/remove_unused_imports.py to automatically remove unused imports.
SubscriberApi.java:192: error: Line is longer than 100 characters (found 102).
SubscriberApi.java:509: error: Line is longer than 100 characters (found 101).
SubscriberApi.java:631: error: Line is longer than 100 characters (found 102).
SubscriberSettings.java:225: error: Line is longer than 100 characters (found 101).
SubscriberSettings.java:319:7: warning: Name 'LIST_SUBSCRIPTIONS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
PublisherApi.java:36:8: error: Unused import: com.google.api.gax.grpc.ApiCallSettings. Use /google/src/head/depot/google3/tools/java/remove_unused_imports.py to automatically remove unused imports.
PublisherApi.java:189: error: Line is longer than 100 characters (found 101).
PublisherSettings.java:289:7: warning: Name 'LIST_TOPICS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
PublisherSettings.java:314:7: warning: Name 'LIST_TOPIC_SUBSCRIPTIONS_PAGE_STR_DESC' must match pattern '^[a-z][a-zA-Z0-9]*_?$'.
Audit done.