Include pcre package to fix wget dyld not founding libpcre

tombar@Erebor ~> wget google.com
dyld: Library not loaded: /opt/boxen/homebrew/lib/libpcre.1.dylib
  Referenced from: /opt/boxen/homebrew/bin/wget
  Reason: image not found
fish: Job 1, 'wget google.com' terminated by signal SIGTRAP (Trace or breakpoint trap)