Removed Travis and Greetings workflows (#415)

* removed greetings workflow, and travis

* Update the build status badge to point to Github Actions

.github/workflows/greetings.yml

@@ -1,14 +0,0 @@
-name: Greetings
-
-on: [pull_request, issues]
-
-jobs:
-  greeting:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/first-interaction@v1
-      with:
-        repo-token: ${{ secrets.GITHUB_TOKEN }}
-        issue-message: "Hola! @${{ github.actor }} 🥳 , You've just created an Issue!🌟 Thanks for making the Project Better"
-        pr-message: 'Submitted a PR already ?? @${{ github.actor }} . Sit tight until one of our amazing maintainers review it. Make sure you read the contributing guide'
- 

.travis.yml

@@ -1,21 +0,0 @@
-group: travis_latest
-language: python
-cache: pip
-python:
-    - "3.6"
-    - "3.7"
-    - "3.8"
-    - "3.9"
-install:
-  - pip install -r requirements.txt
-  - pip install -r requirements-dev.txt
-before_script:
-  - make lint-check
-script:
-  - make test
-after_success:
-  -  bash <(curl -s https://codecov.io/bash)
-notifications:
-  email:
-    on_success: change
-    on_failure: always

README.md

@@ -1,6 +1,6 @@
 ![kube-hunter](https://github.com/aquasecurity/kube-hunter/blob/master/kube-hunter.png)
 
-[![Build Status](https://travis-ci.org/aquasecurity/kube-hunter.svg?branch=master)](https://travis-ci.org/aquasecurity/kube-hunter)
+[![Build Status](https://github.com/aquasecurity/kube-hunter/workflows/Test/badge.svg)](https://github.com/aquasecurity/kube-hunter/actions)
 [![codecov](https://codecov.io/gh/aquasecurity/kube-hunter/branch/master/graph/badge.svg)](https://codecov.io/gh/aquasecurity/kube-hunter)
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 [![License](https://img.shields.io/github/license/aquasecurity/kube-hunter)](https://github.com/aquasecurity/kube-hunter/blob/master/LICENSE)