[VOL-3860] redis client support in voltha-lib-go

redis client support has been added in this patch. There are two
types client `redis` and `redis-sentinel` to connect a redis instance.
redis-sentinel is required to be able to find the master redis
instance from a redis-sentinel process. See redis-sentinel usage
https://redis.io/topics/sentinel and
https://pkg.go.dev/github.com/go-redis/redis/v8#NewFailoverClient
for more information. If there is no need to have any failover
mechanism then the redis client type is the option to choose.

Change-Id: I997ed92115a9d565df632c6dd8184b9bab77b991
diff --git a/go.sum b/go.sum
index 9742906..089ba86 100644
--- a/go.sum
+++ b/go.sum
@@ -46,6 +46,8 @@
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 github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
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+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
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@@ -72,6 +74,8 @@
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+github.com/go-redis/redis/v8 v8.3.4 h1:ZF7juZS2wzxloqMKslTutWJ05IQrnchCSk1HD4d4Vbs=
+github.com/go-redis/redis/v8 v8.3.4/go.mod h1:jszGxBCez8QA1HWSmQxJO9Y82kNibbUmeYhKWrBejTU=
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@@ -107,6 +111,7 @@
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
@@ -184,10 +189,12 @@
 github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=
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+github.com/onsi/ginkgo v1.14.2/go.mod h1:iSB4RoI2tjJc9BBv4NKIKWKya62Rps+oPG/Lv9klQyY=
 github.com/onsi/ginkgo v1.16.4 h1:29JGrr5oVBm5ulCWet69zQkzWipVXIol6ygQUe/EzNc=
 github.com/onsi/ginkgo v1.16.4/go.mod h1:dX+/inL/fNMqNlz0e9LfyB9TswhZpCVdJM/Z6Vvnwo0=
 github.com/onsi/gomega v1.7.1/go.mod h1:XdKZgCCFLUoM/7CFJVPcG8C1xQ1AJ0vpAezJrB7JYyY=
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+github.com/onsi/gomega v1.10.3/go.mod h1:V9xEwhxec5O8UDM77eCW8vLymOMltsqPVYWrpDsH8xc=
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 github.com/opencord/voltha-protos/v5 v5.2.2 h1:1Bcgl+Fmp00ZxlDrHZdcbjpMgOwX6TnZmOTrYm9SbR8=
@@ -262,6 +269,8 @@
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 go.etcd.io/etcd v3.3.25+incompatible h1:V1RzkZJj9LqsJRy+TUBgpWSbZXITLB819lstuTFoZOY=
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+go.opentelemetry.io/otel v0.13.0 h1:2isEnyzjjJZq6r2EKMsFj4TxiQiexsM04AVhwbR/oBA=
+go.opentelemetry.io/otel v0.13.0/go.mod h1:dlSNewoRYikTkotEnxdmuBHgzT+k/idJSfDv/FxEnOY=
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@@ -314,6 +323,7 @@
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+golang.org/x/net v0.0.0-20201006153459-a7d1128ccaa0/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
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@@ -346,6 +356,7 @@
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