Move default spinner, notifications and confirm dialog into a separate package

[amourzenkov-sc]

Package name: uiGlobalComponents. Exports:

1. Object uiSpinner with two methods: show, hide. Each method accepts no arguments and increments/decrements the Component's internal state. The Component is created dynamically, not beforehand.
2. Object uiMessageNotification with four methods: error, success, warning, info. Each method accepts the only named argument ({ message }). A timeout is hardcoded.
3. Function uiModelDialog with the following arguments: ({ title, message, buttons: [{ label, onClick }, ...] }).

[estambakio-sc]

Demo: https://opuscapita.github.io/react-crudeditor/branches/issue-234(slash)uiComponents/?currentComponentName=ContractEditor&maxContainerWidth=100%25&showSidebar=false

Here spinner & notifications are moved out of crud library.