Release 0.25.0

Released 2022-05-17 (On the Norwegian Constitution day 🇳🇴).
Progress: 4331 of 6523 tests passed in dart-sass compatibility mode.

* Update minimum supported rust version to 1.49.0 (from 1.45.2).
* `SourceFile.parse()` now returns a `Result<Parsed>` rahter than a
  `Result<Vec<sass::Item>>`, and `Format::write_root` now takes a
  `Parsed` (PR #140).
* `FsFileContext::file` is replaced by `FsFileContext::for_path`,
  which initializes a file context and loads a file from it (PR 137).

* Hopefully improved relative file finding on windows (PR #137).
* Plain css `@import` rules is only allowed [on a few
  condtions](https://sass-lang.com/documentation/at-rules/import#plain-css-imports),
  in other cases an error is reported (Issue #139, PR #137).
* Rsass can now parse (some) plain css as well as scss.  Css files can
  be referenced in `@use` and `@import` directives, as well as in the
  `meta.load-css` mixin (PR #140).
* Make the `calc(...)` function signal an error when args are known to
  be invalid css (PR #138).
* Change `map.deep-merge` to match recent change in dart sass.
* Minor fix in whitespace around at-rules.
* Instrumented attempted file loading with `tracing` (PR #137).
* Fix a typo in LICENSE (Issue #136).
* Update sass-spec test suite to 2022-05-10.
* Make rust version of sass-spec more directory-aware (which fixes one
  of 5825 tests).
* Use a crates badge that actually works.

Thanks to @jonassmedegaard for #136, and to @fasterthanlime for
reporting the problem that #137 attempts to fix.

Author: kaj

Diff for: CHANGELOG.md

@@ -7,7 +7,10 @@ The format is based on
 project adheres to
 [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## Release 0.25.0
+
+Released 2022-05-17 (On the Norwegian Constitution day 🇳🇴).
+Progress: 4331 of 6523 tests passed in dart-sass compatibility mode.
 
 ### Breaking changes
 

Diff for: README.md

@@ -25,7 +25,7 @@ The sass language [is defined in its reference
 doc](http://sass-lang.com/documentation/file.SASS_REFERENCE.html).
 This implementation is incomplete but getting there, if slowly.
 
-Progress: 4013 of 6478 tests passed in dart-sass compatibility mode.
+Progress: 4331 of 6523 tests passed in dart-sass compatibility mode.
 
 If you want a working rust library for sass right now, you may
 be better of with [sass-rs](https://crates.io/crates/sass-rs)

Diff for: src/lib.rs

@@ -24,7 +24,7 @@
 //! doc](http://sass-lang.com/documentation/file.SASS_REFERENCE.html).
 //! This implementation is incomplete but getting there, if slowly.
 //!
-//! Progress: 4013 of 6478 tests passed in dart-sass compatibility mode.
+//! Progress: 4331 of 6523 tests passed in dart-sass compatibility mode.
 //!
 //! If you want a working rust library for sass right now, you may
 //! be better of with [sass-rs](https://crates.io/crates/sass-rs)