Use v2 Discovery API URL when possible, remove google+ code

All newer APIs support a v2 Discovery URL that is preferred.
They have a fallback v1 URL also but in some cases this fallback
discovery file doesn't have all APIs and methods. We will use
v2 for all APIs that support it.

Also remove some old GPlus commands that are deprecated.

src/var.py

@@ -97,6 +97,21 @@ SKUS = {
     u'product': u'Google-Chrome-Device-Management', u'aliases': [u'chrome', u'cdm', u'googlechromedevicemanagement'], u'displayName': u'Google Chrome Device Management'}
   }
 
+# Legacy APIs that use v1 discovery. Newer APIs should all use v2.
+V1_DISCOVERY_APIS = {
+  u'oauth2',
+  u'reseller',
+  u'storage',
+  u'drive',
+  u'admin',
+  u'groupssettings',
+  u'licensing',
+  u'calendar',
+  u'appsactivity',
+  u'siteVerification',
+  u'gmail',
+  }
+
 API_VER_MAPPING = {
   u'alertcenter': u'v1beta1',
   u'appsactivity': u'v1',
@@ -111,7 +126,6 @@ API_VER_MAPPING = {
   u'groupssettings': u'v1',
   u'licensing': u'v1',
   u'oauth2': u'v2',
-  u'plus': u'v1',
   u'pubsub': u'v1',
   u'reports': u'reports_v1',
   u'reseller': u'v1',
@@ -132,7 +146,6 @@ API_SCOPE_MAPPING = {
   u'gmail': [u'https://mail.google.com/',
              u'https://www.googleapis.com/auth/gmail.settings.basic',
              u'https://www.googleapis.com/auth/gmail.settings.sharing',],
-  u'plus': [u'https://www.googleapis.com/auth/plus.me',],
   u'sheets': [u'https://www.googleapis.com/auth/spreadsheets',],
 }
 
@@ -166,9 +179,6 @@ SERVICE_NAME_CHOICES_MAP = {
   u'googledrive': u'Drive and Docs',
   u'gdrive': u'Drive and Docs',
   u'calendar': u'Calendar',
-  u'gplus': u'Google+',
-  u'google+': u'Google+',
-  u'googleplus': u'Google+',
   }
 
 PRINTJOB_ASCENDINGORDER_MAP = {