Do not pack git files when loading external git repository with extension

[matyaskopp]

Currently, this appears in PMLTQ extension, which is loaded with:

TrEd-extensions/.make.d/pmltq

Lines 1 to 12 in 61adcae

	cd pmltq
	if [ -d .git ]; then
	echo "updating pmltq extension, removing all local changes !!!"
	git reset --hard
	git pull
	else
	echo "clonning pmltq extension from github"
	git init
	git remote add origin git@github.com:ufal/tred-extension-pmltq.git
	git fetch
	git checkout -t origin/master
	fi

possible solutions are:

1. use git archive instead of cloning the repository
2. remove(/do not pack) hidden files from pmltq folder