Address PR change requests

- Fixed misspelling introduced in CONTRIBUTING.md
- Remove `quickchecking -h` output from README.md

Author: shnewto

CONTRIBUTING.md

@@ -227,7 +227,7 @@ See [./csmith-fuzzing/README.md](./csmith-fuzzing/README.md) for details.
 
 ### Property tests for `bindgen` with `quickchecking`
 
-The `tests/quickchecking` crate genertates property tests for `bindgen`.
+The `tests/quickchecking` crate generates property tests for `bindgen`.
 From the crate's directory you can run the tests with `cargo run`. For details
 on additional configuration including how to preserve / inspect the generated 
 property tests, see 

tests/quickchecking/README.md

@@ -35,25 +35,5 @@ Run `quickchecking` binary to generate and test fuzzed C headers with
 
 ```
 $ cargo run --bin=quickchecking -- -h
-quickchecking 0.2.0
-Bindgen property tests with quickcheck. Generate random valid C code and pass it to the csmith/predicate.py script
-
-USAGE:
-    quickchecking [OPTIONS]
-
-FLAGS:
-    -h, --help       Prints help information
-    -V, --version    Prints version information
-
-OPTIONS:
-    -c, --count <COUNT>    Count / number of tests to run. Running a fuzzed header through the predicate.py script can
-                           take a long time, especially if the generation range is large. Increase this number if you're
-                           willing to wait a while. [default: 2]
-    -p, --path <PATH>      Optional. Preserve generated headers for inspection, provide directory path for header
-                           output. [default: None] 
-    -r, --range <RANGE>    Sets the range quickcheck uses during generation. Corresponds to things like arbitrary usize
-                           and arbitrary vector length. This number doesn't have to grow much for execution time to
-                           increase significantly. [default: 32]
-
 ```
 [quickcheck]: https://github.com/BurntSushi/quickcheck