Modal, Button, Lookup improvements

• Modal: Fix Empty Footer, Prompt Support
• Button: disabled, destructive, and inverse props and fixes
• Lookup progress

Add size and directional props to modal

• New Modal properties
• Added UMD build: 'dist' folder

PicklistBase fix

• Removed form tag from PicklistBase

SLDSUtilityIcon component

• SLDSUtilityIcon component: with inlined svg: easier to use and better performance
• SLDS Button improvements and more tests
• SLDSModal fixes

Added new button component

• Created accessible button component that renders base, neutral, brand, and icon variants (inverse, stateful, hint, icon more coming soon)
• Button component with icons use Icon component
• Lightning Design System Reference: https://www.lightningdesignsystem.com/components/buttons

Remove SLDSModal from export

• Remove SLDSModal from export : Temporary fix: there is some dependency issue there

SLDS Module return focus on close

• SLDS Module return focus on close fix

SLDSModal progress / SLDSPicklistBase PropTypes

• SLDSPicklistBase PropTypes / fixes
• SLDSModal progress

removed react-dom dependency

• removed react-dom dependency
• SLDSButton in SLDS index

Picklist Base onClick fix

• Picklist Base onClick fix
• SLDSButton sample code