Add Contributor License Agreement (CLA) assistant (#111)

* Add Contributor License Agreement (CLA) assistant

* Add cla.md

* Update cla.md file path

* Add Entity Contributor License Agreement

* Add Contributor Agreements to contributing.md

.github/workflows/cla.yml

@@ -0,0 +1,43 @@
+name: "CLA Assistant"
+on:
+    issue_comment:
+        types: [created]
+    pull_request_target:
+        types: [opened, closed, synchronize]
+
+# explicitly configure permissions, in case your GITHUB_TOKEN workflow permissions are set to read-only in repository settings
+permissions:
+    actions: write
+    contents: write # this can be 'read' if the signatures are in remote repository
+    pull-requests: write
+    statuses: write
+
+jobs:
+    CLAAssistant:
+        runs-on: ubuntu-latest
+        steps:
+            - name: "CLA Assistant"
+              if: (github.event.comment.body == 'recheck' || github.event.comment.body == 'I have read the CLA Document and I hereby sign the CLA') || github.event_name == 'pull_request_target'
+              uses: contributor-assistant/github-action@v2.4.0
+              env:
+                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+                  # the below token should have repo scope and must be manually added by you in the repository's secret
+                  # This token is required only if you have configured to store the signatures in a remote repository/organization
+                  PERSONAL_ACCESS_TOKEN: ${{ secrets.PERSONAL_ACCESS_TOKEN }}
+              with:
+                  path-to-signatures: "docs/signatures/cla.json"
+                  path-to-document: "https://github.com/opengeos/HyperCoast/blob/main/docs/cla.md" # e.g. a CLA or a DCO document
+                  # branch should not be protected
+                  branch: "main"
+                  allowlist: user1,bot*
+
+                  # the following are the optional inputs - If the optional inputs are not given, then default values will be taken
+                  #remote-organization-name: enter the remote organization name where the signatures should be stored (Default is storing the signatures in the same repository)
+                  #remote-repository-name: enter the  remote repository name where the signatures should be stored (Default is storing the signatures in the same repository)
+                  #create-file-commit-message: 'For example: Creating file for storing CLA Signatures'
+                  #signed-commit-message: 'For example: $contributorName has signed the CLA in $owner/$repo#$pullRequestNo'
+                  #custom-notsigned-prcomment: 'pull request comment with Introductory message to ask new contributors to sign'
+                  #custom-pr-sign-comment: 'The signature to be committed in order to sign the CLA'
+                  #custom-allsigned-prcomment: 'pull request comment when all contributors has signed, defaults to **CLA Assistant Lite bot** All Contributors have signed the CLA.'
+                  #lock-pullrequest-aftermerge: false - if you don't want this bot to automatically lock the pull request after merging (default - true)
+                  #use-dco-flag: true - If you are using DCO instead of CLA