JSON type can be bound to a package

[AkimitsuTosha]

issue

#1149

Test

$ cat manifest.yaml    
project:
  packages:
    package1:
      inputs:
        param1:
          key1: value1
          key2: value2
      actions:
        action1:
          function: ./action1.js
          runtime: nodejs
$ go build -o ./wskdeploy
$ ./wskdeploy --preview
Packages:
Name: package1
    bindings: 
        - param1 : {
  "key1": "value1",
  "key2": "value2"
}
    annotation: 

  * action: action1
    bindings: 
    annotation: 


Triggers:

Rules