Compile a set of regexps for files to be exlcuded from scans.

def compile_excludes(self):
        """Compile a set of regexps for files to be exlcuded from scans."""
        self.compiled_exclude_files = []
        for pattern in self.exclude_files:
            try:
                self.compiled_exclude_files.append(re.compile(pattern))
            except re.error as e:
                raise ValueError(
                    "Bad python regex in exclude '%s': %s" % (pattern, str(e)))