Release new minor version 0.4.0 due to bumped cortex-m dependency

Signed-off-by: Daniel Egger <daniel@eggers-club.de>

Author: therealprof

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+## [v0.4.0] - 2019-04-12
+
 ### Added
 
 - API to enable and disable SPI interrupts
@@ -17,6 +19,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Implement reading the device electronic signature from flash
 
+### Changed
+
+- [breaking-change] Updated cortex-m dependency to v0.6.0.
+
 ## [v0.3.0] - 2019-01-14
 
 ### Added
@@ -157,7 +163,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Support for stm32f407 and stm32f429.
 
-[Unreleased]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.3.0...HEAD
+[Unreleased]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.4.0...HEAD
+[v0.4.0]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.3.0...v0.4.0
 [v0.3.0]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.2.8...v0.3.0
 [v0.2.8]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.2.7...v0.2.8
 [v0.2.7]: https://github.com/stm32-rs/stm32f4xx-hal/compare/v0.2.6...v0.2.7

Cargo.toml

@@ -19,14 +19,14 @@ license = "0BSD"
 name = "stm32f4xx-hal"
 readme = "README.md"
 repository = "https://github.com/stm32-rs/stm32f4xx-hal"
-version = "0.3.0"
+version = "0.4.0"
 
 [package.metadata.docs.rs]
 features = ["stm32f429", "rt"]
 
 [dependencies]
-cortex-m = "0.5.8"
-cortex-m-rt = "0.6.7"
+cortex-m = "0.6.0"
+cortex-m-rt = "0.6.8"
 nb = "0.1.1"
 stm32f4 = "0.6.0"