v0.19.0

This release now includes a statically linked tarball!
It should work as-is when uncompressed on any amd64 linux system.

Language changes:

• Unused definitions and arguments generate warnings
  • These warnings can be made fatal with --fatal-warnings
• There is now a v0_19_wake stable API package
  • Production wake files should from v0_19_wake import _
  • These files should then continue to work as the API changes

Standard library changes:

• Comparison of NaNs no longer panic, following IEEE rules
• Large Vectors and Integers no longer panic, unlimited size
• Jobs now have an optional Label to control progress display
• New functions: append, prepend, sortPaths

Runtime changes:

• linux systems leverage unshare for isolation
  • This eliminates the '.fuse' directory from build paths
  • Resources fed to the FUSE runner can control unshare
• wake.db is now versioned and detects when incompatible
• When no package is inferred, use an empty package importing wake

Bugfixes:

• Symbol listing ('-g' or '-e') works on large projects
• Unary + and +. are now properly typed
• Missing Tree type was exported
• Work-around for a non-empty .fuse directory added