v1.2.1

Bugfix release.

• Can combine flags, -bm now does the same as -b -m
• [ms] many many stability fixes for invalid inputs
• [ms] support for demangling MSVC's noexcept types
• [ms] support for operator<=> demangling
• [ms] operator co_await now demangled as operator co_await, not
  co_await
• [ms] correct \x escapes in char16_t, wstring_t, char32_t literals
• [ms] \0 characters in string literals are now demangled as \0, not \x00;
  better string literal demangling heuristic for strings with \0s
• [ms] correctly demangle vararg parameters
• [ms] support demangling char8_t
• [ms] support demangling local static thread guards
• [itanium] support for block literals
• [itanium] support gcc "old-style unified" ctor and dtor manglings
• [itanium] vendor extended types demangling fix
• [itanium] support for demangling __uuidof expressions

Binaries are now built by the new dist.py script.