Little tweaks

[djlauk]

I came along these minor issues:

dismissable vs dismissible

According to dictionary.com it is the latter spelling.

Affected components:

• mega-snackbar
• mega-drawer

fullwidth vs full-width

The attribute is full-width in the @property declaration of both mega-button and mega-textfield, but in the CSS (and demo) of the textfield, attribute was fullwidth instead. (which just didn't bind to anything.)

Affected components:

• mega-textfield