Update tracing/opentracing/DOC.md (grpc-ecosystem#136)

* Update DOC.md

* fix typo

Author: liukgg

tracing/opentracing/DOC.md

@@ -69,7 +69,7 @@ new span.
 ``` go
 func StreamClientInterceptor(opts ...Option) grpc.StreamClientInterceptor
 ```
-StreamClientInterceptor returns a new streaming server interceptor for OpenTracing.
+StreamClientInterceptor returns a new streaming client interceptor for OpenTracing.
 
 ## <a name="StreamServerInterceptor">func</a> [StreamServerInterceptor](./server_interceptors.go#L37)
 ``` go
@@ -81,7 +81,7 @@ StreamServerInterceptor returns a new streaming server interceptor for OpenTraci
 ``` go
 func UnaryClientInterceptor(opts ...Option) grpc.UnaryClientInterceptor
 ```
-UnaryClientInterceptor returns a new unary server interceptor for OpenTracing.
+UnaryClientInterceptor returns a new unary client interceptor for OpenTracing.
 
 ## <a name="UnaryServerInterceptor">func</a> [UnaryServerInterceptor](./server_interceptors.go#L23)
 ``` go
@@ -115,4 +115,4 @@ func WithTracer(tracer opentracing.Tracer) Option
 WithTracer sets a custom tracer to be used for this middleware, otherwise the opentracing.GlobalTracer is used.
 
 - - -
-Generated by [godoc2ghmd](https://github.com/GandalfUK/godoc2ghmd)
+Generated by [godoc2ghmd](https://github.com/GandalfUK/godoc2ghmd)

tracing/opentracing/client_interceptors.go

@@ -17,7 +17,7 @@ import (
 	"google.golang.org/grpc/metadata"
 )
 
-// UnaryClientInterceptor returns a new unary server interceptor for OpenTracing.
+// UnaryClientInterceptor returns a new unary client interceptor for OpenTracing.
 func UnaryClientInterceptor(opts ...Option) grpc.UnaryClientInterceptor {
 	o := evaluateOptions(opts)
 	return func(parentCtx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
@@ -31,7 +31,7 @@ func UnaryClientInterceptor(opts ...Option) grpc.UnaryClientInterceptor {
 	}
 }
 
-// StreamClientInterceptor returns a new streaming server interceptor for OpenTracing.
+// StreamClientInterceptor returns a new streaming client interceptor for OpenTracing.
 func StreamClientInterceptor(opts ...Option) grpc.StreamClientInterceptor {
 	o := evaluateOptions(opts)
 	return func(parentCtx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {