[Feature] Semver Ranges

[Naratzul]

[Work in progress]

It's a draft implementation of semver ranges. It's already supports basic range comparators like

• >=1.2.7
• >=1.2.0 <=2.3.4

Example

const semver::range range(">= 1.2.4 < 2.0.0");
constexpr semver::version version = "1.5.2"_version;
if (range.contains(version)) {
  // do something
}

What I'm going to do next:

• support prerelease tags
• support range set chaining by ||
• support advanced range syntax (hyphen, caret, tilde, etc)
• make it constexpr if possible

Any suggestions and improvements are welcome.