Inital implmentation of RateLimitChecker

This is a stripped down rate limit checking implmentation that handles the infrastructure
of deciding how to get rate limit information and leaves it to other implementers to
decided what kind of checks they want to do and how long they want to wait.

The implmentation supports checkers that sleep less than the full time until the
rate limit is expected to reset, allowing for polling and notifying clients of why their query
is not returning.

A basic checker which sleeps until the rate limit is expected to reset is included as working example..

src/main/java/org/kohsuke/github/GitHubClient.java

@@ -6,7 +6,6 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.PropertyNamingStrategy;
 import com.fasterxml.jackson.databind.introspect.VisibilityChecker;
 import org.apache.commons.lang3.StringUtils;
-import org.jetbrains.annotations.NotNull;
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
@@ -64,6 +63,7 @@ abstract class GitHubClient {
 
     protected final RateLimitHandler rateLimitHandler;
     protected final AbuseLimitHandler abuseLimitHandler;
+    private final GitHubRateLimitChecker rateLimitChecker;
 
     private HttpConnector connector;
 
@@ -95,6 +95,7 @@ abstract class GitHubClient {
             HttpConnector connector,
             RateLimitHandler rateLimitHandler,
             AbuseLimitHandler abuseLimitHandler,
+            GitHubRateLimitChecker rateLimitChecker,
             Consumer<GHMyself> myselfConsumer) throws IOException {
 
         if (apiUrl.endsWith("/")) {
@@ -124,6 +125,7 @@ abstract class GitHubClient {
 
         this.rateLimitHandler = rateLimitHandler;
         this.abuseLimitHandler = abuseLimitHandler;
+        this.rateLimitChecker = rateLimitChecker;
 
         if (login == null && encodedAuthorization != null && jwtToken == null) {
             GHMyself myself = fetch(GHMyself.class, "/user");
@@ -336,6 +338,8 @@ abstract class GitHubClient {
                                     + " " + request.url().toString());
                 }
 
+                rateLimitChecker.checkRateLimit(this, request);
+
                 responseInfo = getResponseInfo(request);
                 noteRateLimit(responseInfo);
                 detectOTPRequired(responseInfo);
@@ -366,7 +370,7 @@ abstract class GitHubClient {
         throw new GHIOException("Ran out of retries for URL: " + request.url().toString());
     }
 
-    @NotNull
+    @Nonnull
     protected abstract GitHubResponse.ResponseInfo getResponseInfo(GitHubRequest request) throws IOException;
 
     protected abstract void handleLimitingErrors(@Nonnull GitHubResponse.ResponseInfo responseInfo) throws IOException;
@@ -442,7 +446,7 @@ abstract class GitHubClient {
     /**
      * Sets the response headers on objects that need it. Ideally this would be handled by the objects themselves, but
      * currently they do not have access to {@link GitHubResponse.ResponseInfo} after the
-     * 
+     *
      * @param responseInfo
      *            the response info
      * @param readValue