[CI] enabled boot from +brass pill

.travis.yml

@@ -9,13 +9,18 @@ node_js:
 #   email: false
 
 before_install:
+  #  try to get pill early, so configuration errors will be quickly caught
+  #
+  - cd .travis
+  - bash get-brass-pill.sh
+  - cd ..
   - wget https://github.com/ninja-build/ninja/releases/download/v1.8.2/ninja-linux.zip
   - unzip ninja-linux.zip
   - sudo mv ninja /usr/bin/
 
 install:
   # pwd: ~/urbit
-  - pip3 install --user -I meson==0.44.1
+  - pip3 install --user -I meson
 
 script:
   - meson . ./build --buildtype=debugoptimized -Dgc=true -Dprof=true

.travis/get-brass-pill.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+set -euo pipefail
+set -x
+
+if [ ! -f ./pin-brass-pill.txt ]; then
+  echo "missing .travis/pin-brass-pill.txt"
+  exit 1
+fi
+
+PILL_NAME=$(cat ./pin-brass-pill.txt | tr -d [:space:])
+
+wget https://bootstrap.urbit.org/$PILL_NAME -O brass.pill && exit 0
+
+echo "$PILL_NAME download failed"
+exit 1

.travis/pin-arvo-commit.txt

@@ -1 +0,0 @@
-6d6ec85d6aa9200d366d0998326726ef1965d092

.travis/pin-brass-pill.txt

@@ -0,0 +1 @@
+urbit-0.7.2.brass.pill

.travis/test.js

@@ -6,10 +6,7 @@ var Urbit   = runner.Urbit;
 var ERROR   = runner.ERROR;
 var actions = runner.actions
 
-var hash  = fs.readFileSync('./pin-arvo-commit.txt', 'utf-8').slice(0, 10)
-var pill  = 'https://bootstrap.urbit.org/git-' + hash + '.pill'
-
-var args  = ['-u', pill, '-cgPSF', 'zod', 'zod'];
+var args  = ['-cgPSF', 'zod', '-B', 'brass.pill', 'zod'];
 var urbit = new Urbit(args);
 
 // vere hangs (always?) with run in travis-ci with -P