Don't run the readme check for subprojects

The superproject should have a readme, but it's not necessarily essential for the subproject to have one as well.

Author: per1234

Diff for: check/checkfunctions/checkfunctions.go

@@ -69,6 +69,10 @@ func containsIncorrectPathBaseCase(pathList paths.PathList, correctBaseName stri
 
 // MissingReadme checks if the project has a readme that will be recognized by GitHub.
 func MissingReadme() (result checkresult.Type, output string) {
+	if checkdata.ProjectType() != checkdata.SuperProjectType() {
+		return checkresult.NotRun, "Readme not required for subprojects"
+	}
+
 	// https://github.com/github/markup/blob/master/README.md
 	readmeRegexp := regexp.MustCompile(`(?i)^readme\.(markdown)|(mdown)|(mkdn)|(md)|(textile)|(rdoc)|(org)|(creole)|(mediawiki)|(wiki)|(rst)|(asciidoc)|(adoc)|(asc)|(pod)|(txt)$`)
 

Diff for: check/checkfunctions/checkfunctions_test.go

@@ -64,6 +64,7 @@ func checkCheckFunction(checkFunction Type, testTables []checkFunctionTestTable,
 
 func TestMissingReadme(t *testing.T) {
 	testTables := []checkFunctionTestTable{
+		{"Subproject", "readme", projecttype.Sketch, projecttype.Library, checkresult.NotRun, ""},
 		{"Readme", "readme", projecttype.Sketch, projecttype.Sketch, checkresult.Pass, ""},
 		{"No readme", "no-readme", projecttype.Sketch, projecttype.Sketch, checkresult.Fail, ""},
 	}