Autoscaler concurrency annotations are added to the revision template if
--min-scale / --max-scale / --concurrency-target/--concurrency-limit
are provided to `kn service create` and `kn service update`
Fixes#151
Creates four subpackages for now:
1. kn/commands - inludes types.go for common
struct and other common files and misc commands
2. kn/commands/service - all 'kn service *' commands
3. kn/commands/revision - all 'kn revision *' commands
4. kn/core - contains the root.go and other top level
for code and testing
5. refactors:
a. split .../commons/human_readable_flags.go into three
b. modifies the HumanReadableFlags.ToPrinter to get pass
a function that sets the columns and fields
Had to refactor all tests to avoid cycles.
dr.max