Add install script for installing from source.

This commit adds an install script that installs all stactools
subpackages from source. Installing stactools from github with all the
subprojects isn't possible, so this allows other projects to clone
this repo and run this script in order to obtain unpublished stactools changes.

scripts/cibuild

@@ -24,15 +24,7 @@ if [ "${BASH_SOURCE[0]}" = "${0}" ]; then
         python -m pip install --upgrade pip
         pip install -r requirements-dev.txt
 
-        for PACKAGE_DIR in "${STACTOOLS_SUBPACKAGE_DIRS[@]}"
-        do
-            pushd ./${PACKAGE_DIR}
-            pip install -e .
-            popd
-
-        done
-
-        pip install -e .[all]
+        ./scripts/install
 
         ./scripts/test
     fi

scripts/install

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+set -e
+
+if [[ -n "${CI}" ]]; then
+    set -x
+fi
+
+# Import shared variables
+source ./scripts/env
+
+function usage() {
+    echo -n \
+        "Usage: $(basename "$0")
+Install all stactools packages.
+"
+}
+
+if [ "${BASH_SOURCE[0]}" = "${0}" ]; then
+    if [ "${1:-}" = "--help" ]; then
+        usage
+    else
+        for PACKAGE_DIR in "${STACTOOLS_SUBPACKAGE_DIRS[@]}"
+        do
+            pushd ./${PACKAGE_DIR}
+            pip install -e .
+            popd
+
+        done
+
+        pip install -e .[all]
+    fi
+fi