corrected keywords

Author: jbrodovsky

core/Cargo.toml

@@ -8,7 +8,7 @@ license = "MIT"
 readme = "README.md"
 homepage = "https://www.strapdown.rs"
 repository = "https://www.github.com/jbrodovsky/strapdown-rs"
-keywords = ["strapdown", "inertial navigation", "navigation", "IMU", "INS"]
+keywords = ["strapdown", "inertial", "navigation", "IMU", "INS"]
 categories = ["navigation", "robotics", "aerospace", "engineering"]
 documentation = "https://docs.rs/strapdown-rs/"