Make project directory a variable.

Turn $1 into a named variable
clone into created directory. remove unneeded commands because of that.
use $HOME instead of ~ so that it works when quoted
use -p for mkdir so that it will generate the full path to the new dir if need be. also so it wont error if the dir already exists.
check that a project name has been passed to the script
protect against spaces in project name
catch non quoted project names
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Merge pull request #1 from rjw1/master

improvements