env: downgrade zipp to restore compatibility with python3.4 & python3.5

https://travis-ci.org/github/fphammerle/free-disk/jobs/675620053#L198
https://travis-ci.org/github/fphammerle/free-disk/jobs/675620056#L198

.gitignore

@@ -3,6 +3,7 @@
 *.pyc
 .*.sw[op]
 .coverage
+.mypy_cache/
 .pytest_cache/
 __pycache__/
 build/

Pipfile

@@ -22,6 +22,9 @@ pylint-import-requirements = "*"
 # v5.0.0 dropped python3.4. support
 # https://github.com/pytest-dev/pytest/commit/4d49ba65297102110ae8aeecdb3b82b23a231fba
 pytest = "<5"
+# v2.0.0 dropped python<3.6 support
+# https://github.com/jaraco/zipp/commit/05a3c52b4d41690e0471a2e283cffb500dc0329a
+zipp = "<2"
 
 [requires]
 python_version = "3"

Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "d8973779657116b8ede343b55895ef6bf504cc136979dc54c38ca74185f92c0e"
+            "sha256": "cd9a09c062d0b2a9106bda5599bdeb22f87e060b9741d8837c9d09ec01de4bab"
         },
         "pipfile-spec": 6,
         "requires": {
@@ -201,10 +201,11 @@
         },
         "zipp": {
             "hashes": [
-                "sha256:aa36550ff0c0b7ef7fa639055d797116ee891440eac1a56f378e2d3179e0320b",
-                "sha256:c599e4d75c98f6798c509911d08a22e6c021d074469042177c8c86fb92eefd96"
+                "sha256:c70410551488251b0fee67b460fb9a536af8d6f9f008ad10ac51f615b6a521b1",
+                "sha256:e0d9e63797e483a30d27e09fffd308c59a700d365ec34e93cc100844168bf921"
             ],
-            "version": "==3.1.0"
+            "index": "pypi",
+            "version": "==1.2.0"
         }
     }
 }