Add AxisCamera wrapper class.

This takes hosts (IP or DNS name) rather than URLs, making it easier
to use.

Also add more overloads to resolve ambiguities encountered when using
std::string and const char*, and also add overloads for
std::initializer_list<T> so braced initializer lists can be used.

java/src/edu/wpi/cscore/AxisCamera.java

@@ -0,0 +1,37 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2016. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+package edu.wpi.cscore;
+
+/// A source that represents an Axis IP camera.
+public class AxisCamera extends HttpCamera {
+  private static String hostToUrl(String host) {
+    return "http://" + host + "/mjpg/video.mjpg";
+  }
+
+  private static String[] hostToUrl(String[] hosts) {
+    String[] urls = new String[hosts.length];
+    for (int i = 0; i < hosts.length; i++) {
+      urls[i] = hostToUrl(hosts[i]);
+    }
+    return urls;
+  }
+
+  /// Create a source for an Axis IP camera.
+  /// @param name Source name (arbitrary unique identifier)
+  /// @param host Camera host IP or DNS name (e.g. "10.x.y.11")
+  public AxisCamera(String name, String host) {
+    super(name, hostToUrl(host), CameraKind.kAxis);
+  }
+
+  /// Create a source for an Axis IP camera.
+  /// @param name Source name (arbitrary unique identifier)
+  /// @param hosts Array of Camera host IPs/DNS names
+  public AxisCamera(String name, String[] hosts) {
+    super(name, hostToUrl(hosts), CameraKind.kAxis);
+  }
+}