add bump-version.sh script and update contributing.md

bump-version.sh is there to make it easier to changes version number when doing release.
It upates version number in README.md, cmd/version.go and install.sh.

scripts/bump-version.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+
+
+# this scripts updates version number in ocdev source code
+# run this script from source root with new version as an argument (./scripts/bump-version.sh v0.0.2 )
+
+NEW_VERSION=$1
+
+if [[ -z "${NEW_VERSION}" ]]; then
+    echo "Version number is missing."
+    echo "One argument required."
+    echo "example: $0 v0.0.2"
+    exit 1
+fi
+
+check_version(){
+    file=$1
+    
+    grep ${NEW_VERSION} $file
+    echo ""
+}
+
+echo "* Bumping version in README.md"
+sed -i "s/v[0-9]*\.[0-9]*\.[0-9]*/${NEW_VERSION}/g" README.md
+check_version README.md
+
+echo "* Bumping version in cmd/version.go"
+sed -i "s/\(VERSION = \)\"v[0-9]*\.[0-9]*\.[0-9]*\"/\1\"${NEW_VERSION}\"/g" cmd/version.go
+check_version cmd/version.go
+
+echo "* Bumping version in scripts/install.sh"
+sed -i "s/\(LATEST_VERSION=\)\"v[0-9]*\.[0-9]*\.[0-9]*\"/\1\"${NEW_VERSION}\"/g" scripts/install.sh
+check_version scripts/install.sh
+
+echo "****************************************************************************************"
+echo "* Don't forget to update homebrew package at https://github.com/kadel/homebrew-ocdev ! *"
+echo "****************************************************************************************"
+