mark urbit executable executable

.travis.yml

@@ -4,6 +4,7 @@ before_install:
   
   # XX use an actual debian release, based on version pin somewhere
   - wget https://github.com/ohAitch/urbit/releases/download/untagged-4dd5d7e977e58b5f1e21/urbit
+  - chmod +x ./urbit
   
   # XX don't just blindly assume master
   - >

.travis/test.ls

@@ -2,6 +2,7 @@ require! \stream-snitch
 pty = require \pty.js
 
 term =
+  # TODO abort on failure
   # XX use -s instead of travis wget'd pill
   pty.spawn './urbit' <[-B urbit.pill -A .. -cFI zod zod]> 
      .on \data -> process.stdout.write it