[Build Tools] Meteor package: Use api.addAssets for static files

[gimco]

Description

Trying add the semantic-ui package to a meteor project raise the next error:

$ meteor add semantic:ui-css

 => Errors while adding packages:             
                                              
While building package semantic:ui-css:
error: No plugin known to handle file 'themes/default/assets/fonts/icons.eot'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/fonts/icons.eot', 'client').
error: No plugin known to handle file 'themes/default/assets/fonts/icons.svg'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/fonts/icons.svg', 'client').
error: No plugin known to handle file 'themes/default/assets/fonts/icons.ttf'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/fonts/icons.ttf', 'client').
error: No plugin known to handle file 'themes/default/assets/fonts/icons.woff'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/fonts/icons.woff', 'client').
error: No plugin known to handle file 'themes/default/assets/fonts/icons.woff2'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/fonts/icons.woff2', 'client').
error: No plugin known to handle file 'themes/default/assets/images/flags.png'. If you want this file to be a static asset, use addAssets instead of addFiles; eg,
api.addAssets('themes/default/assets/images/flags.png', 'client').

Since meteor 1.2 api.addAsset should be used to define static files. So this pull request simple use addAsset for static files and addFiles to files whose must be processed by the framework.

Related Issues

Semantic-Org/Semantic-UI-CSS#14
Semantic-Org/Semantic-UI-CSS#18
Semantic-Org/UI-Flag#1
Semantic-Org/UI-Icon#5

[jlukic]

This looks good to me. Sorry about the delay.