Added ability to apply multiple presets

[Fsss126]

What was done

• Added support for specifying multiple presets
• Strongly typed presets config

Description

Multiple presets can be applied to component by passing an array, support for passing a string as it was before remains

<VaButton
    :preset="['addToCart', 'promotion']"
/>

createVuestic({
  components: {
    presets: {
      VaButton: {
        addToCart: { round: true, color: 'success', icon: 'shopping_cart', 'slot:default': 'Add to card' },
        promotion: { gradient: true, color: 'primary' }
      },
    },
  },
})

Presets can extend each other - if one preset specifies preset prop they will be recursively applied. This code will produce the same as above

createVuestic({
  components: {
    presets: {
      VaButton: {
        addToCart: { round: true, color: 'success', icon: 'shopping_cart', 'slot:default': 'Add to card' },
        promotion: { preset: 'addToCart', gradient: true, color: 'primary' }
      },
    },
  },
})

<VaButton
    preset="promotion"
/>

Extending multiple presets is also supported.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Improvement/refactoring (non-breaking change that doesn't add any feature but make things better)

[m0ksem]

We also need stories.