Error occurred in deployment step 'Add Solution': Use the force attribute to explicitly re-install the feature

Problem
Error occurred in deployment step 'Add Solution':
A feature with ID 15/59ad6e04-ffe4-46da-acbf-927d4eb5e3ba has already been installed in this farm.  Use the force attribute to explicitly re-install the feature.

Solution
You can do it via the XML editor as well!

Steps:
1. Go to your Features in your project.
2. Open the feature.template.xml file with XML Editor View
3. add AlwaysForceInstall="TRUE" to the below tag

Applicable to 
Sharepoint 2013/ 2010