feat(core): add support for composite tasks

[Codelax]

This is an helper library that allows to split a command in tasks and print the execution to the user, this also provides a way to cleanup after a failed task

Usage:

ts := tasks.Begin()
ts.AddWithCleanUp("Creating container namespace", func(i interface{}) (interface{}, interface{}, error) {
	time.Sleep(time.Second)
	return i, "data", nil
}, func(i interface{}) error {
	// i == "data"
	fmt.Println("clean " + i.(string)
	return nil
})
ts.Add("Creating container", func(i interface{}) (interface{}, error) {
	time.Sleep(time.Second * 2)
	return i, fmt.Errorf("error")
})
ts.Add("Pushing image", func(i interface{}) (interface{}, error) {
	time.Sleep(time.Second * 3)
	return i, nil
})
ts.Add("Deploying", func(i interface{}) (interface{}, error) {
	time.Sleep(time.Second * 3)
	return i, nil
})

Result:

[1/4] Creating container namespace
[2/4] Creating container
<cool interactive loading spinner>

then

[1/4] Creating container namespace
[2/4] Creating container
task failed, cleaning up created resources
[1/4] Cleaning task "Creating container namespace"
clean data
Task 2 "Creating container" failed: error

[codecov-commenter]

Codecov Report

Merging #2596 (128eafe) into master (a04acb7) will increase coverage by 0.00%.
The diff coverage is 77.90%.

@@           Coverage Diff           @@
##           master    #2596   +/-   ##
=======================================
  Coverage   74.58%   74.59%           
=======================================
  Files         142      144    +2     
  Lines       28716    28802   +86     
=======================================
+ Hits        21417    21484   +67     
- Misses       6558     6576   +18     
- Partials      741      742    +1     

Impacted Files	Coverage Δ
internal/tasks/tasks.go	75.64% <75.64%> (ø)
internal/tasks/loader.go	100.00% <100.00%> (ø)

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[Codelax]

Tasks states could be stored, this state could be exported to terraform state