Files containing spaces in their path are wrongly encoded (timols#331) (timols#332)

- Encode '+' characters in paths in '%20'

Author: slauriere

src/main/java/org/gitlab/api/GitlabAPI.java

@@ -3290,7 +3290,7 @@ private String sanitizeId(Serializable id, String parameterName) {
 
     private String sanitizePath(String branch) {
         try {
-            return URLEncoder.encode(branch, "UTF-8");
+            return URLEncoder.encode(branch, "UTF-8").replaceAll("\\+", "%20");
         } catch (UnsupportedEncodingException e) {
             throw new RuntimeException((e));
         }