Add fix-suggestion - Githubissues

.some
{
   color: rgb(255, 0, 255, 1);
}

In this example, alpha component is excess and validator will tell about it: Mismatch syntax But, will be cool if validator will suggesting some fixes for these (and similar) cases:

fixes: [
  'rgb(255, 0, 255);',
  'rgba(255, 0, 255, 1);'
]

Some other examples:

add missed unit
```
.some
{
width: 10;
}
```
```
fixes: [
'10px'
]
```

fix mistyped

.some
{
coor: rgb(255, 0, 255, 1);
}

fixes: [
'color'
]

csstree / validator

Add fix-suggestion #5