Exit code is 0 when warnings/errors are found

gulp-csslint does not seem to be setting an error code on exit, even if errors are found in the tested CSS file.

For instance, with the following CSS file:

.foo {
  width: 300px

The following is the output and exit code from csslint's CLI tool:

$ csslint test.css; echo $?

csslint: There are 2 problems in D:\Documents\git\test2\test.css.

test.css
1: error at line 4, col 1
Expected RBRACE at line 4, col 1.

test.css
2: error at line 4, col 1
Expected RBRACE at line 4, col 1.

1

Whereas gulp-css gives the same output with an exit code of 0.

lazd / gulp-csslint

Exit code is 0 when warnings/errors are found #64