Update travis

Should use git when building tape-benchmark
Test travis
Test travis #2
Test travis #3
Travis fix

Should fix: Use of uninitialized value $ref in concatenation (.) or
string at ./script/git-head.pl line 17.

Test: Use of uninitialized value $branch in scalar chomp at
./script/version.pl line 11.
Travis fix #4
Travis: fix warning 'printf'

Add new warning flag: -Wformat-security
Test new script
Link to -lrt if needed
Add missing progs for travis