scanner/http/crawler: added ExcludePathPatterns opt

Option 'ExcludePathPatterns' allows users to specify which paths should
be excluded from the crawl (and which forms to ignore) by passing a
list of patterns (only allows '*' wildcards).
Merge remote-tracking branch 'upstream/master' into feature/web_crawler_skip_paths
Merge branch 'feature/web_crawler_skip_paths' of github.com:tasos-r7/metasploit-framework into tasos-r7-feature/web_crawler_skip_paths
Merge branch 'tasos-r7-feature/web_crawler_skip_paths'