Added the ability to replace some placeholders in the screeps code (#12)

added the `git-replace` option.
Replaceing {{gitRef}}, {{deployTime}} and {{gitHash}}.

Reviewed-on: #12
Co-authored-by: Philipp Horstenkamp <philipp@horstenkamp.de>
Co-committed-by: Philipp Horstenkamp <philipp@horstenkamp.de>

action.yaml

@@ -37,6 +37,9 @@ inputs:
     description: 'Branch in Screeps to which the code will be uploaded (default: default).'
     required: false
     default: default
+  git-replace:
+    description: Allows for the overwrite of the "{{gitRef}}", "{{gitHash}}" and "{{deployTime}}" values in the file matching the file pattern. The file pattern will be combined with the prefix.
+    required: false
 runs:
   using: node12
   main: index.js