refactor Resource / Threshold into its own crate, drop task!, tweak rtfm::atomic

task! can be re-added in a backward compatible fashion and I'd like to not have
two ways to assign a task handler to an interrupt / exception in the first
release.

rtfm::atomic now uses the `Threshold` token instead of the `CriticalSection`
token. This reduces overhead by dropping the "are interrupts enabled?" check.

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 392538b..8ce7bdb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,6 +15,7 @@ version = "0.2.0"
 [dependencies]
 cortex-m = "0.3.1"
 static-ref = "0.2.1"
+rtfm-core = { git = "https://github.com/japaric/rtfm-core" }
 
 [dependencies.cortex-m-rtfm-macros]
 path = "macros"