Change pipeline config path resolution (#299)

# Config resolution
- pipeline-config setting empty / not specified (default): `.woodpecker/` => `.woodpecker.yml` => `.drone.yml`
- pipeline-config setting defined by user: try that file / folder and no fallback (if a user sets some special value that is normally done for some reason)

# Changes
- pipeline-config setting will be empty by default
- remove fallback setting for config loading (simplifies config)

---
closes #133

---

* adjust config fetching mechanism

* default path empty

* remove fallback flag from ui and db

web/src/screens/repo/screens/settings/index.js

@@ -41,7 +41,6 @@ export default class Settings extends Component {
     this.handleVisibilityChange = this.handleVisibilityChange.bind(this);
     this.handleTimeoutChange = this.handleTimeoutChange.bind(this);
     this.handlePathChange = this.handlePathChange.bind(this);
-    this.handleFallbackChange = this.handleFallbackChange.bind(this);
     this.handleChange = this.handleChange.bind(this);
   }
 
@@ -74,14 +73,6 @@ export default class Settings extends Component {
               value={repo.config_file}
               onBlur={this.handlePathChange}
             />
-            <label>
-              <input
-                type="checkbox"
-                checked={repo.fallback}
-                onChange={this.handleFallbackChange}
-              />
-              <span>Fallback to .drone.yml if path not exists</span>
-            </label>
           </div>
         </section>
         <section>
@@ -231,10 +222,6 @@ export default class Settings extends Component {
     this.handleChange("config_file", e.target.value);
   }
 
-  handleFallbackChange(e) {
-    this.handleChange("fallback", e.target.checked);
-  }
-
   handleChange(prop, value) {
     const { dispatch, drone, repo } = this.props;
     let data = {};