fix references to old tester directory

.gitlab-ci.yml

@@ -42,14 +42,14 @@ job-build-test:
 job-build-ext_tester:
   stage: build
   script:
-    - cd ext_tester
+    - cd tester
 
 job-build-test-ext:
   stage: test
   script:
     - ./configure.sh
     - make
-    - cd ext_tester
+    - cd tester
     - make run
 
 workflow:

README.md

@@ -115,13 +115,13 @@ $ ./bin/mojitos -t 5 -f 1 -p cpu_cycles -r -s
 ```
 
 ## Testing
-MojitO/S provides a utility for correctness testing. It is located in the ext_tester directory and can be expanded easily with new tests.  
-This utility requires `mojitos` to be built first, and can then be ran by running `make run` in the ext_tester directory.  
+MojitO/S provides a utility for correctness testing. It is located in the `tester` directory and can be expanded easily with new tests.  
+This utility requires `mojitos` to be built first, and can then be ran by running `make run` in the tester directory.  
 
 It works by running `mojitos` multiple times with different parameters, and running its output through different verification functions each time. 
 
 ### Adding tests  
-A complete explanation on how to use the testing API can be found [here](./ext_tester/readme.md)
+A complete explanation on how to use the testing API can be found [here](./tester/readme.md)
 
 
 ## License