Client-side-validation v0.12.0

The new client-side validation library comes with a fully re-worked single-use seals library, and a number of improvements and issue fixes for the commit_verify library.

What's Changed

• Client-side validation v0.12 base by @dr-orlovsky in #187
• Add more reserved types to STL by @dr-orlovsky in #191
• Rebase improvements from v0.11 by @dr-orlovsky in #193
• Revision for the release v0.12 by @dr-orlovsky in #195
• Fixes and improvements by @dr-orlovsky in #194

Full Changelog: v0.11.0...v0.12.0