The reason they exist is because you are using the VS Code Solidity extension. One feature of this extension is that it enables Solium (now Ethlint). This is a linter that checks your code for errors and warnings, such as
no-trailing-whitespace: Line contains trailing whitespace.
The best solution is to fix these warnings in your code, since the warnings are suggestions to follow best practices when writing Solidity. Code that follows the Solidity style guide should have no warnings like this.
If you want to remove some of these warnings without changing the code, you will need to edit your
settings.json in VS Code. Within this file you can add the following line:
In here, you can add rules that you want to ignore. For example, if you want to ignore the trailing whitespace warning, your
settings.json file should look as follows: