Rename scan to scanText for consistency (#21)

Author: evanfuller

README.md

@@ -82,7 +82,7 @@ try (NightfallClient c = NightfallClient.Builder.defaultClient()) {
     ScanTextConfig config = ScanTextConfig.fromDetectionRuleUUIDs(Arrays.asList(rule), 20);
     ScanTextRequest req = new ScanTextRequest(payload, config);
 
-    ScanTextResponse response = c.scan(req);
+    ScanTextResponse response = c.scanText(req);
     System.out.println("findings: " + response.getFindings());
 }
 ```

src/main/java/ai/nightfall/scan/NightfallClient.java

@@ -87,7 +87,7 @@ public void close() {
      * @throws IllegalArgumentException thrown if <code>request</code> is null
      * @throws NightfallRequestTimeoutException thrown if the request is aborted because the timeout is exceeded
      */
-    public ScanTextResponse scan(ScanTextRequest request) {
+    public ScanTextResponse scanText(ScanTextRequest request) {
         if (request == null) {
             throw new IllegalArgumentException("request must be non-null");
         }