1.3.0

Special thanks to @billyzkid, as this release is almost entirely based on his contributions, including the PRs he submitted and the issues he highlighted.

New:

• Adds support for auto-detection of arguments supplied in nested functions.

Fixed:

• Resolves "unbound variable" errors when getopts_long is used with set -u
• Aligns the behaviour of OPTARG between the builtin getopts and getopts_long
• Upgrades all tests to use declare instead of echo

Full Changelog: 1.2.3...1.3.0