Improved Task Execution

In earlier forms, Devlab would parse a called task from the config and join any line-breaks with &&. While this worked it was sub-optimal as it would cause issues when multiple tasks with multiple lines were chained together. This release fixes the issue by instead creating a temporary devlab.sh, based on any running task definitions, in the project root which is then executes upon that. After execution the devlab.sh file is removed.