Refactor start scripts

[ronilaukkarinen]

Project start scripts have been refactored completely same manner than in this PR.

Changes:

• Add working WSL support (documentation), linked also to windows-lemp-setup
• Modularize bash scripts, add files as partials. From now on we need to edit files under bin/tasks. Only couple of files are different, for example sed commands for debian and macOS vary, that's why
• Beautiful formatting and instructions for the start script (header.sh, footer.sh)
• Prevent running directly with bash or sh to prevent possible issues with them
• Variable all the things - no need to search and replace stuff
• Fix typos
• Add checks for missing packages (WSL mainly)
• Add extra notifications that these scripts need Air-light and dev servers to work

[ronilaukkarinen]

macOS version tested successfully just now.

[ronilaukkarinen]

This was a mistake. Will revert in the morning.