Rearranged CI configuration and added Julia versions 1.1 - 1.3

.gitlab-ci.yml

-Julia 1.0:
+variables:
+    JULIA_DEPOT_PATH: "$CI_PROJECT_DIR/.julia"
+
+.test_template: &test_definition
+  script:
+    - mkdir -p "$CI_PROJECT_DIR/.julia" && ls -al "$CI_PROJECT_DIR/.julia"
+    - julia -e 'using Pkg; Pkg.clone(pwd()); Pkg.build("KM3io"); Pkg.test("KM3io"; coverage = true)'
+    - julia -e 'using Pkg; Pkg.add("Coverage"); 
+      import KM3io; cd(joinpath(dirname(pathof(KM3io)), ".."));
+      using Coverage; cl, tl = get_summary(process_folder());
+      println("(", cl/tl*100, "%) covered")'
+    - ls -al "$CI_PROJECT_DIR/.julia"
+
+cache:
+  paths:
+    - "$CI_PROJECT_DIR/.julia"
+  key: "$CI_COMMIT_REF_SLUG"
+
+test:julia-1.0:
   image: julia:1.0
-  script: julia --project='@.' -e 'using Pkg; Pkg.build(); Pkg.test(; coverage=true)'
-  coverage: /Test Coverage (\d+\.\d+%)/
-  after_script:
-    - julia -e 'using Printf; using Pkg; Pkg.add("Coverage"); using Coverage; c, t = get_summary(process_folder()); @printf "Test Coverage %.2f%%\n" 100c/t'
+  <<: *test_definition
+
+test:julia-1.1:
+  image: julia:1.1
+  <<: *test_definition
+
+test:julia-1.2:
+  image: julia:1.2
+  <<: *test_definition
+
+test:julia-1.3:
+  image: julia:1.3
+  <<: *test_definition
+
 pages:
-  image: julia:1.0
+  image: julia:1.3
   stage: deploy
   script:
     - julia --project=docs -e '