check for dig and adjusts dependency check logic

[mwoolweaver]

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What does this PR aim to accomplish?:

• adds check for dig command

• adjusts the logic for dependency check to check for all 3 before exiting.

How does this PR accomplish the above?:

check_dependencies() {
    local hasDeps=true
    # Check for required dependencies
    if ! command -v curl >/dev/null 2>&1; then
        printf "%b" "${check_box_bad} Error!\n    'curl' is missing but required.\n"
        hasDeps=false
    fi

    if ! command -v jq >/dev/null 2>&1; then
        printf "%b" "${check_box_bad} Error!\n    'jq' is missing but required.\n"
        hasDeps=false
    fi

    if ! command -v dig >/dev/null 2>&1; then 
        printf "%b" "${check_box_bad} Error!\n    'dig' is missing but required.\n" 
        hasDeps=false
     fi

     if ! command -v tput >/dev/null 2>&1; then 
        printf "%b" "${check_box_bad} Error!\n    'tput' is missing but required.\n" 
        hasDeps=false
     fi

     if [ "${hasDeps}" = false ]; then 
        printf "%b" "\n Please install the dependencies noted above.\n" 
        exit 1
     fi
}

fixes #455

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[darkexplosiveqwx]

ncurses is required for getting the size of the terminal. Specifically the tput command from that package.

[mwoolweaver]

ncurses is required for getting the size of the terminal. Specifically the tput command from that package.

added as well