Opam fix (#6)

Prep for opam

Author: UnixJunkie

Makefile

@@ -134,6 +134,7 @@ remove:
 
 .PHONY: clean
 clean:
+	rm -rf static_libs
 	dune clean
 
 $(BUILT_C_FILES): _build/%.c: %.c

dune

@@ -7,7 +7,7 @@
 (library
  (name hack_parallel)
  (public_name hack_parallel)
- (c_library_flags -lhp)
+ (c_library_flags -L static_libs -l hp)
  (libraries
   str
   core

hack_parallel.opam

@@ -5,7 +5,10 @@ homepage: "https://github.com/rvantonder/hack-parallel"
 bug-reports: "https://github.com/rvantonder/hack-parallel/issues"
 dev-repo: "git+https://github.com/rvantonder/hack-parallel.git"
 license: "MIT"
-build: ["dune" "build" "-p" name "-j" jobs "@install"]
+build: [
+  [make "libhp.a"]
+  ["dune" "build" "-p" name "-j" jobs "@install"]
+]
 depends: [
   "core"
   "ppx_deriving"