Fix build on macOS

Overview

macOS directory is not case senstative. It gets confused when there is a file name VERSION and a directory called version and there are conflicts which prevents macOS users from building the application.

Remove the version package since we don't really need packages for a 2 file application.

How to test

1. Compile the application make compile

   make compile

   $ make compile
   go build \
                           -o build/tlsctl \
                           -ldflags "-X main.VERSION=0.1.0-beta-22-g1e52941 -X main.REVISION=1e52941 -X main.BRANCH=fix-versions-macos -X main.BUILT=2021-02-04T09:26:55+0000 -s -w" \
                           .

2. Print the version ./build/tlsctl -v

   ./build/tlsctl -v

   $ ./build/tlsctl -v
   tlsctl
   Version:      0.1.0-beta-22-g1e52941
   Git revision: 1e52941
   Git branch:   fix-versions-macos
   GO version:   go1.15.5
   Built:        2021-02-04T09:26:55+0000
   OS/Arch:      darwin/amd6

3. Print help text ./build/tlsctl -h

   ./build/tlsctl -h

   $ ./build/tlsctl help
   NAME:
      tlsctl - Set of commands to debug TLS certificates for GitLab Runner.
   
   USAGE:
      tlsctl [global options] command [command options] [arguments...]
   
   VERSION:
      0.1.0-beta-22-g1e52941 (1e52941)
   
   DESCRIPTION:
      Set of commands to debug TLS certificates for GitLab Runner.
   
   AUTHOR:
      GitLab Inc. <support@gitlab.com>
   
   COMMANDS:
      save     Use GitLab Runner TLS verification and save the chain in a file
      info     Print information about each cert in a chain.
      chain    Print the chain of a certificate.
      help, h  Shows a list of commands or help for one command
   
   GLOBAL OPTIONS:
      --help, -h     show help
      --version, -v  print the version