ENH: Compile git with SSL support

Older versions of git included in older linux distributions are not able
to download source from Github. A newer version is required with a newer
OpenSSL. This requires to also build curl with the same OpenSSL.

CMake is downloaded precompiled if available (64bits system) or compiled
from source otherwise.

imagefiles/build-and-install-git.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+set -ex
+
+if ! command -v curl &> /dev/null; then
+	echo >&2 'error: "curl" not found!'
+	exit 1
+fi
+
+if ! command -v tar &> /dev/null; then
+	echo >&2 'error: "tar" not found!'
+	exit 1
+fi
+
+if [[ "${GIT_VERSION}" == "" ]]; then
+  echo >&2 'error: GIT_VERSION env. variable must be set to a non-empty value'
+  exit 1
+fi
+
+(cat /etc/ld.so.conf.d/usr-local.conf 2> /dev/null | grep -q "^/usr/local/lib$") ||
+  echo '/usr/local/lib' >> /etc/ld.so.conf.d/usr-local.conf
+ldconfig
+
+cd /usr/src
+
+url="https://www.kernel.org/pub/software/scm/git/git-${GIT_VERSION}.tar.gz"
+echo "Downloading $url"
+curl -# -LO $url
+
+tar xvzf git-${GIT_VERSION}.tar.gz
+rm -f git-${GIT_VERSION}.tar.gz
+
+pushd git-${GIT_VERSION}
+./configure --prefix=/usr/local --with-curl
+make
+make install
+popd
+
+ldconfig
+
+rm -rf git-${GIT_VERSION}
+
+# turn the detached message off
+git config --global advice.detachedHead false