Refactored tools structure & conventions for reuse (#685)

1.  All common tools are hosted and managed in
    the tools directory (used for both local development
    and continuous integration)
2.  Each tool comprises a directory, akin to a bundle,
    that encapsulates declarative command-line options,
    configuration files and a run script
3.  A single bootstrap script configures a
    development environment
4.  A lightweight runtime provides a common set of
    convenience functions and variables to all scripts

References #672

.tools/hooks/pre-commit.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# instantiate mysensors tool runtime shim
+. "$(git mystoolspath).bundle_runtime.sh"
+
+###
+#  astyle 
+#
+errorsDetected=0
+for file in $(stagedSourceFiles); do
+	git astyle $file >/dev/null
+	if ! git diff-files --quiet $file >&2; then
+		warn "$file has been updated to match the MySensors core coding style."
+		errorsDetected=1
+	fi
+done
+
+[ $errorsDetected == 1 ] && err "Styling updates applied. Review the changes and use 'git add' to update your staged files."
+
+###
+#  cppcheck
+#
+errorsDetected=0
+for file in $(stagedSourceFiles); do
+	if ! git cppcheck $file >/dev/null; then
+		warn "$file failed static analysis."
+		errorsDetected=1
+	fi
+done
+
+[ $errorsDetected == 1 ] && err "Correct the errors until cppcheck passees using 'git cppcheck --cached'."
+
+exit 0