Release v1.4.0 alpha 3

What's Changed

• Fixes #76. Python 3.7 is end-of-life by @markfinal in #77
• Fixes #81. Custom submenus no longer overwriting parent menu by @markfinal in #82
• Fixes #62. Simple way to specify dependency options by @foundry-markf in #85
• Can specify package version if not available by other means by @markfinal in #87
• Fixes #84. During recipe load, display the failure when an invalid pa… by @markfinal in #88
• Fixes #80. Conan2. Implement getting the Conan environment variables by @markfinal in #89
• Fixes #78. Conan 2. Replaced conan_run implementation with a streamin… by @markfinal in #90

Full Changelog: v1.4.0a2...v1.4.0a3