Merge branch 'master' into test-staged-binaries

CHANGELOG.md

@@ -3,6 +3,8 @@
 # Master
 
 - Test staged binaries on Travis
+- Unpin Heroku-18 binary build deps
+- Typo fixes
 
 --------------------------------------------------------------------------------
 

bin/steps/pip-uninstall

@@ -13,7 +13,7 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
 
 
     if ! pip-diff --stale requirements-declared.txt requirements.txt --exclude setuptools pip wheel > .heroku/python/requirements-stale.txt; then
-      mount "failure.bad-requirements"
+      mcount "failure.bad-requirements"
     fi
 
     rm -fr requirements-declared.txt

builds/heroku-18.Dockerfile

@@ -7,7 +7,7 @@ ENV WORKSPACE_DIR="/app/builds" \
     DEBIAN_FRONTEND=noninteractive \
     STACK="heroku-18"
 
-RUN apt-get update && apt-get install --no-install-recommends -y python-pip-whl=9.0.1-2 python-pip=9.0.1-2 python-setuptools python-wheel && rm -rf /var/lib/apt/lists/*
+RUN apt-get update && apt-get install -y python-pip && rm -rf /var/lib/apt/lists/*
 
 COPY requirements.txt /app/
 RUN pip install --disable-pip-version-check --no-cache-dir -r /app/requirements.txt