Add GitIgnore to existing Repository.

Readme.text

Step 1: Mannually add git ignore file on git server with predefine templates for ex. if you are adding gitignore file in 
        iOS project than user Object-C template.
Step 2: After successfully adding git ignore update your local branch code with latest code.
Step 3: While Merging master code with local code may be you will see VIM editor to add commit message. So for VIM editor 
        Just press ESC -> : -> x it will close VIM editor. After than perform 
        Git add .
        Git commit -m "COMMIT MESSAGE"
        Git Push origin "BRANCH_NAME"
Step 4: After you run your project you will still see the untracked files. To remove those files perform following setps.
        May be in your repository you will see any other file so below path is just for reference please don't take it seriousally
        other wise you will be in trouble. 
        i:  git rm --cached ProjectFolder.xcodeproj/project.xcworkspace/xcuserdata/myUserName.xcuserdatad/UserInterfaceState.xcuserstate
        ii: git commit -m "Removed file that shouldn't be tracked"
Step 5: After performing above steps again add, commit and push to server branch.
Step 6: FINISH