chdir to server root at server boot
implemented server_setup: now it can be specified the server root (useful in tests)
test server_setup
refactor: replace all print with log: info, debug, warning, error and critical, and write in to a crash_report.log file the errors and criticals logs.
Merge branch 'test_refactoring' of https://github.com/fmarco/share-system-team1 into test_refactoring

Conflicts:
	server/server.py
tests: make headers as indipendent function
typo in make_headers
tests: refactored test_create_user
tests: some fixes (missing import, delete temp file only if needed)
tests: refactored test_md5
refactored post test
Merge branch 'test_refactoring' of https://github.com/fmarco/share-system-team1 into test_refactoring
tests: removed obsolete tests
refactoring files api
Merge branch 'test_refactoring' of https://github.com/fmarco/share-system-team1 into test_refactoring
add pep 8 #r Please enter the commit message for your changes. Lines starting
Merge branch 'test_refactoring' of https://github.com/fmarco/share-system-team1 into test_refactoring
tests: refactored test_add_share
added refactored put test, some fixes to do
refactoring