Go modules dependency fetching doesn't work

[Johan Håkansson]

1:

>> go version
go version go1.14.1 linux/amd64

2:

>> git clone https://github.com/lalamove/konfig && cd konfig

3:

>> go mod download
go: contrib.go.opencensus.io/exporter/ocagent@v0.4.6 requires
	github.com/census-instrumentation/opencensus-proto@v0.1.0-0.20181214143942-ba49f56771b8: invalid pseudo-version: version before v0.1.0 would have negative patch number

[Nishaad Ajani]

Hello, this is now fixed in #63