Enable hot reloading for docker-compose runs

[juozasget]

Closes #11

• Added Dockerfile.dev to use for hot-reloading.
• Added make build.dev to explicitly use go modules and avoid error from vendor folder.

> Step 8/8 : ENTRYPOINT CompileDaemon --build="make build" --command=./bin/r2d2
 ---> Running in dd13e49ddb0a
Removing intermediate container dd13e49ddb0a
 ---> 887d62ef9693

Successfully built 887d62ef9693
Successfully tagged r2-d2_r2d2:latest
Starting dynamodb-local ... done
Recreating r2-d2        ... done
Attaching to dynamodb-local, r2-d2
dynamodb-local | Initializing DynamoDB Local with the following configuration:
dynamodb-local | Port:  8000
dynamodb-local | InMemory:  false
dynamodb-local | DbPath:    /home/dynamodblocal
dynamodb-local | SharedDb:  true
dynamodb-local | shouldDelayTransientStatuses:  false
dynamodb-local | CorsParams:    *
dynamodb-local |
r2-d2       | 2020/09/30 20:41:30 Running build command!
r2-d2       | 2020/09/30 20:41:30 Error while building:
r2-d2       |  GO111MODULE=on go build -o bin/r2-d2 internal/*.go
r2-d2       | go: inconsistent vendoring in /build:
r2-d2       |   github.com/fatih/color@v1.9.0: is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt
r2-d2       |   github.com/fsnotify/fsnotify@v1.4.9: is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt
r2-d2       |   github.com/githubnemo/CompileDaemon@v1.2.1: is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt
r2-d2       |
r2-d2       | run 'go mod vendor' to sync, or use -mod=mod or -mod=readonly to ignore the vendor directory
r2-d2       | make: *** [Makefile:93: build] Error 1
r2-d2       |```

[juozasget]

Looks like go get -u github.com/golangci/golangci-lint/cmd/golangci-lint is not working. https://github.com/kubernetes-sigs/azuredisk-csi-driver/pull/369

Looks like the reccommended way is: https://golangci-lint.run/usage/install/#ci-installation "We recommend running this action in a job separate from other jobs (go test, etc) because different jobs run in parallel."

Don't want to impose changes to CI, so leaving this for you @ghostwriternr :)

[juozasget]

Happy to help! Kudos for very nice and approachable project setup!