Update version to v0.1.0 and add CHANGELOG.md

Several repositories using Yorkie had version issues. It has not yet
been released to users, but is pre-released for version control.

CHANGELOG.md

@@ -0,0 +1,31 @@
+# Changelog
+
+All notable changes to Yorkie will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and Yorkie adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [0.1.0] - 2020-11-07
+
+First public release
+
+### Added
+ - Add basic structure of Yorkie such as `Document`, `Client`, and Agent(`yorkie`)
+ - Add Custom CRDT data type `Text` for code editor: #2
+ - Add Snapshot API to reduce payload: #9
+ - Add Garbage Collection to clean CRDT meta: #3
+ - Add Custom CRDT data type `RichText` for WYSIWYG editor: #7
+ - Add Peer Awareness API: #48
+ - Add Prometheus metrics: #76
+ - Add Custom CRDT data type `Counter`: #82
+
+### Changed
+
+### Removed
+
+### Deprecated
+
+[Unreleased]: https://github.com/yorkie-team/yorkie/compare/v0.1.0...HEAD
+[0.1.0]: https://github.com/yorkie-team/yorkie/releases/tag/v0.1.0# 

Makefile

@@ -1,7 +1,9 @@
-YORKIE_VERSION := 0.0.12
+YORKIE_VERSION := 0.1.0
 
 GIT_COMMIT := $(shell git rev-parse --short HEAD)
 
+DATE := $(shell date "+%Y-%m-%d")
+
 GO_PROJECT = github.com/yorkie-team/yorkie
 
 GO_SRC := $(shell find . -path ./vendor -prune -o -type f -name '*.go' -print)
@@ -20,6 +22,7 @@ GO_LDFLAGS ?=
 # inject the version number into the golang version package using the -X linker flag
 GO_LDFLAGS += -X ${GO_PROJECT}/pkg/version.GitCommit=${GIT_COMMIT}
 GO_LDFLAGS += -X ${GO_PROJECT}/pkg/version.Version=${YORKIE_VERSION}
+GO_LDFLAGS += -X ${GO_PROJECT}/pkg/version.BuildDate=${DATE}
 
 EXECUTABLE = ./bin/yorkie
 

cmd/version.go

@@ -17,6 +17,7 @@ func newVersionCmd() *cobra.Command {
 			fmt.Printf("Yorkie: %s\n", version.Version)
 			fmt.Printf("Commit: %s\n", version.GitCommit)
 			fmt.Printf("Go: %s\n", runtime.Version())
+			fmt.Printf("Build date: %s\n", version.BuildDate)
 			return nil
 		},
 	}

pkg/version/version.go

@@ -7,4 +7,7 @@ var (
 
 	// The main version number that is being run at the moment.
 	Version = "0.0.0"
+
+	// The date the executable was built.
+	BuildDate string
 )