linux: Switch from pyinstaller root image to one built off manylinux

Can't use the vanilla manylinux images because CPython isn't built as shared.
koordinates2/manylinux2014-pyshared images are a minor tweak.
See pypa/manylinux#1185 for details.

After that just install PyInstaller into the image before running.

Manylinux2014-derived libraries use libxcrypt to provide libcrypt.so.2, but that
doesn't seem to end up bundled. Do it manually. Probably goes away with a newer
PyInstaller.

kart.spec

@@ -118,7 +118,6 @@ pyi_analysis = Analysis(
     noarchive=False,
 )
 
-# Git
 if is_win:
     pyi_analysis.datas += Tree('vendor/dist/git', prefix='git')
     # GDAL/osgeo hook doesn't include Proj
@@ -131,6 +130,9 @@ else:
     libexec_root = 'vendor/dist/env/libexec'
     pyi_analysis.datas += Tree('vendor/dist/env/share', prefix='share')
 
+if is_linux:
+    pyi_analysis.binaries += [('libcrypt.so.2', '/usr/local/lib/libcrypt.so.2', 'BINARY')]
+
 pyi_pyz = PYZ(pyi_analysis.pure, pyi_analysis.zipped_data, cipher=None)
 
 if is_win:

platforms/Makefile

@@ -57,9 +57,8 @@ pyapp-Linux: $(SRC)/vendor/dist/vendor-Linux.tar.gz
 		-v "$(SRC):/src" \
 		-w /src \
 		-v "$(abspath linux/.cache):/root/.cache" \
-		--entrypoint "/bin/bash" \
-		cdrx/pyinstaller-linux \
-		-i -c '/src/platforms/linux/pyinstaller.sh $(if $(MANYLINUX_DEBUG),|| bash)'
+		koordinates2/manylinux2014-pyshared:x86_64 \
+		bash -c '/src/platforms/linux/pyinstaller.sh $(if $(MANYLINUX_DEBUG),|| bash)'
 
 $(pyapp-Darwin):
 	$(MAKE) pyapp-Darwin

platforms/linux/pyinstaller.sh

@@ -1,18 +1,25 @@
 #!/bin/bash
-set -ex
+set -e
 
 source /root/.bashrc
 
-PYENV_PREFIX=$(pyenv prefix)
+set -xu
+
+export PATH=/opt/python/cp37-cp37m-shared/bin:${PATH}
+
+python3 --version
+python3 -m venv /venv
+
+export PATH=/venv/bin:${PATH}
 
 { echo ">> Configuring vendor dependencies..."; } 2> /dev/null
 tar xvzf vendor/dist/vendor-Linux.tar.gz -C /tmp wheelhouse
 rm -rf vendor/dist/env/
 tar xzf vendor/dist/vendor-Linux.tar.gz -C vendor/dist/ env
-tar xzf vendor/dist/vendor-Linux.tar.gz -C "$PYENV_PREFIX" --strip-components=1 env/lib/
+tar xzf vendor/dist/vendor-Linux.tar.gz -C /venv --strip-components=1 env/lib/
 
 # get the Rtree installer working successfully
-export SPATIALINDEX_C_LIBRARY="$PYENV_PREFIX/lib/libspatialindex_c.so"
+export SPATIALINDEX_C_LIBRARY="/venv/lib/libspatialindex_c.so"
 
 pip install --no-deps --ignore-installed -r requirements.txt
 pip install --no-deps \
@@ -21,10 +28,10 @@ pip install --no-deps \
 { echo ">> Downgrading PyInstaller (https://github.com/pyinstaller/pyinstaller/issues/4674) ..."; } 2> /dev/null
 pip install "pyinstaller==3.5.*"
 
-python setup.py install
+python3 setup.py install
 
 { echo ">> Pre-bundle Smoke Test ..."; } 2> /dev/null
-pyenv exec kart --version
+kart --version
 
 { echo ">> Running PyInstaller ..."; } 2> /dev/null
 pyinstaller \