Add 'Show license' support to deploy.sh script (#30)

deploy.sh

@@ -9,6 +9,7 @@ Deploy generated files to a git branch.
 Options:
 
   -h, --help               Show this help information.
+  -l, --license            Show BSD-3 license information.
   -v, --verbose            Increase verbosity. Useful for debugging.
   -e, --allow-empty        Allow deployment of an empty directory.
   -m, --message MESSAGE    Specify the message used when committing on the
@@ -30,6 +31,38 @@ overridden by environment variables. Any environment variables are overridden
 by values set in a '.env' file (if it exists), and in turn by those set in a
 file specified by the '--config-file' option."
 
+license_message="\
+BSD 3-Clause License:
+
+Copyright Daniel Smith
+All rights reserved.
+
+Original work: https://github.com/X1011/git-directory-deploy
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimer in the documentation and/or
+  other materials provided with the distribution.
+
+  The names of the contributors may not be used to endorse or promote products
+  derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS' AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+
 parse_args() {
 	# Set args from a local environment file.
 	if [ -e ".env" ]; then
@@ -49,6 +82,9 @@ parse_args() {
 		if [[ $1 = "-h" || $1 = "--help" ]]; then
 			echo "$help_message"
 			return 0
+		elif [[ $1 = "-l" || $1 = "--license" ]]; then
+			echo "$license_message"
+			return 0
 		elif [[ $1 = "-v" || $1 = "--verbose" ]]; then
 			verbose=true
 			shift