Update dependencies

Drop use of core.incubator; start testing against 1.9.0 (master); change
Clojure dependency to "provided" so it isn't dragged into projects as a
transitive dependency and potentially cause conflicts with whatever
version of Clojure those projects want to use.

project.clj

@@ -9,15 +9,16 @@
             :url "http://www.opensource.org/licenses/mit-license.php"
             :distribution :repo}
   :min-lein-version "2.0.0"
-  :dependencies [[org.clojure/core.incubator "0.1.3"]
-                 [org.clojure/data.json "0.2.6"]
+  :dependencies [[org.clojure/data.json "0.2.6"]
                  [org.mongodb/mongo-java-driver "2.14.0"]
-                 [org.clojure/clojure "1.8.0"]]
+                 [org.clojure/clojure "1.8.0" :scope "provided"]]
   ;; if a :dev profile is added, remember to update :aliases below to
   ;; use it in each with-profile group!
   :profiles {:1.3 {:dependencies [[org.clojure/clojure "1.3.0"]]}
              :1.4 {:dependencies [[org.clojure/clojure "1.4.0"]]}
              :1.5 {:dependencies [[org.clojure/clojure "1.5.1"]]}
              :1.6 {:dependencies [[org.clojure/clojure "1.6.0"]]}
-             :1.7 {:dependencies [[org.clojure/clojure "1.7.0"]]}}
-  :aliases {"test-all" ["with-profile" "default:1.3,default:1.4,default:1.5,default:1.6,default:1.7,default" "test"]})
+             :1.7 {:dependencies [[org.clojure/clojure "1.7.0"]]}
+             :1.9 {:repositories [["snapshots" "https://oss.sonatype.org/content/repositories/snapshots/"]]
+                   :dependencies [[org.clojure/clojure "1.9.0-master-SNAPSHOT"]]}}
+  :aliases {"test-all" ["with-profile" "default:1.3,default:1.4,default:1.5,default:1.6,default:1.7,default,default:1.9" "test"]})