remove nova files, add git ignore for .nova files

.gitignore

@@ -1,3 +1,4 @@
 .DS_Store
 __pycache__/
 src/seedsigner.egg-info/
+.nova

.nova/Configuration.json

@@ -1,4 +0,0 @@
-{
-  "workspace.color" : 2,
-  "workspace.name" : "seedsigner"
-}

.nova/Tasks/Custom Task.json

@@ -1,11 +0,0 @@
-{
-  "actions" : {
-    "run" : {
-      "enabled" : true,
-      "script" : "#!\/bin\/sh\n\n# stop systemd service if running\nsudo systemctl stop seedsigner.service\n\n# kill and existing processes\nps -ef | grep \"python3 main.py\" | grep -v grep | awk '{print $2}' | xargs kill\ncd \/home\/pi\/seedsigner\/src\n\/usr\/bin\/python3 main.py"
-    }
-  },
-  "identifier" : "1B30DFE9-3294-4949-8ED8-67E47D15E10B",
-  "openLogOnRun" : "start",
-  "serverName" : "SeedSigner Wifi"
-}