Bump version to v0.0.2-SNAPSHOT

Author: songy23

build.gradle

@@ -7,7 +7,7 @@ apply plugin: 'maven'
 apply plugin: "signing"
 
 group = "io.opencensus"
-version = "0.0.1" // CURRENT_OPENCENSUS_PROTO_VERSION
+version = "0.0.2-SNAPSHOT" // CURRENT_OPENCENSUS_PROTO_VERSION
 
 sourceCompatibility = 1.6
 targetCompatibility = 1.6