fix(scripts): fix validation of current dir

Author: azu

lib/scripts/create-textlint-rule.js

@@ -20,10 +20,10 @@ module.exports = function(projectName, options = {}) {
     const useYes = options.yes !== undefined;
     const isInitInCurrentDir = projectName === ".";
     const ruleName = isInitInCurrentDir
-                     ? path.dirname(projectName)
+                     ? path.basename(options.cwd)
                      : `textlint-rule-${projectName.replace(/^textlint-rule-/, "")}`;
     if (isInitInCurrentDir && !/^textlint-rule-/.test(ruleName)) {
-        throw new Error(`Current directory name should start with "textlint-rule-<rule-name>".`);
+        throw new Error(`Current directory name should start with "textlint-rule-<rule-name>": ${ruleName}.`);
     }
     const ruleDir = isInitInCurrentDir ? options.cwd : path.join(options.cwd, ruleName);
     return spawn(`git`, [