migrating from localhost to server - What to do with the folder sites/localhost.mysitename?
I don't know the acquia product you are using. And I don't know bluehost - but it seems to be a "usual webhoster". I assume at bluehost is an ordinary LAMP stack running without any drupal-specific modifications.

update 2 after comments of EB84:

It turns out you are not using multi-sites. Seems to me as you made your setup more difficult than it needs to be:

Just replace the default folder with your localhost.mysitename folder. By doing so you revert your folder-structure back to a simple single-site setup.

Keep in mind, that you need to adopt your settings.php to the preferences of your bluehost webspace (database parameters, etc.). Your settings.php will look different on the server than on your local machine - all other files and directories may be the same.

update 1 after comment of EB84:

Since you are using a multi-site setup the configuration in sites/sites.php will control which site will be used for what domain names in HTTP requests.

Please read following documents:


https://api.drupal.org/api/drupal/sites!example.sites.php/7
https://drupal.org/documentation/install/multi-site 


You will read that the directory names are arbitrary - as long as you map the domain name of the HTTP requests to it (via the configuration in sites.php).

Anyhow it might be good to remove the term "localhost" from your directory name - not for the whole thing to run technically, but to not confuse yourself some when in future.