removed files from git code example

Example 1: git delete file

// delete unused file. 
// It will be placed on index area, and been deleted at next commit

git rm file-to-delete.ext

Example 2: git remove file

git rm [-f | --force] [-n] [-r] [--cached] [--ignore-unmatch]
	  [--quiet] [--pathspec-from-file=<file> [--pathspec-file-nul]]
	  [--] [<pathspec>…]