Issue 6405 - Remove CircleCI refs.

deploy/checkout-core.sh

-#!/bin/sh
-
-CORE_REPONAME=$1
-MAIN_BRANCH=$2
-ORIGIN_URL=git@github.com:${CIRCLE_PROJECT_USERNAME}/${CORE_REPONAME}.git
-
-pushd ${HOME}
-
-# Kitt-core checkout folder "../kitt-core" is CACHED (see circle.yml).
-# Must cover all 3 possible states of the repo
-if [ -d "${CORE_REPONAME}" ]; then
-# Cached folder does exist
-  cd ${CORE_REPONAME}
-  if [ ! -d ".git" ]; then
-# but has lost git knowledge, recreate it
-    echo "Core folder exists but is not git repo, adding remote"
-    git init
-    git remote add origin ${ORIGIN_URL}
-  fi
-# update from git, original or recreated
-  echo "Fetching core repo origin"
-  git fetch origin
-else
-# Cached folder does not exist (was not in cache yet), create new
-  echo "Core folder does not exist, cloning"
-  git clone ${ORIGIN_URL}
-  cd ${CORE_REPONAME}
-fi
-
-# Check out as similar kitt-core branch as the one of main adblock repo
-if [ "$MAIN_BRANCH" == "master" ]; then
-  # master is already checked out by default upon git clone
-  # (no remote -t)
-  echo "Checking out local master"
-  git checkout -f master
-else
-  # does the same branch exist in kitt-core ?
-  CORE_BRANCH=$(git branch -r | grep "${MAIN_BRANCH}$")
-  if [ -z "$CORE_BRANCH" ]; then
-    echo "Main branch '$MAIN_BRANCH' does not exist in '$CORE_REPONAME'"
-    case "$MAIN_BRANCH" in
-      release* )
-        # fall back to newest release branch
-        # TECHNICALLY OBSOLETE BECAUSE THERE IS ALWAYS ONLY ONE RELEASE BRANCH
-        # WITHOUT VERSION NUMBER but kept for potential future changes
-        CORE_BRANCH=$(git branch -r | grep release | sort -g | tail -1)
-        echo "Will check out latest '$CORE_BRANCH'"
-      ;;
-      *)
-        # fall back to develop
-        echo "Will check out develop head"
-        CORE_BRANCH="origin/develop"
-      ;;
-    esac
-  fi
-  git checkout -f -t $CORE_BRANCH
-fi
-
-popd