Changes in api

- Api functions can define an HTTP method to use to call them. "405 Method Not Allowed" is returned on error
- Api function that modify data accepts only POST as method.
- A list of HTTP return code related exception is added
- Api functions throw HTTP exceptions instead of return false or die()
- api_call() catches HTTP exceptions and return error message with corret HTTP response code
- api_format_items() returns also item activities count (# of like/dislike etc)
- api/friendica/photos/list return more info about photos. xml format added.
- api/friendica/photo/detail return more info, links to all sizes, no data except if 'size' parameter is passed. xml format added.
- new api api/friendica/activity/<verb> and api/friendica/activity/un<verb> to add or remove like/dislike/attend status

include/HTTPExceptions.php

@@ -0,0 +1,105 @@
+<?php
+/**
+ * Throwable exceptions to return HTTP status code
+ *
+ * This list of Exception has be extracted from
+ * here http://racksburg.com/choosing-an-http-status-code/
+ */
+
+class HTTPException extends Exception {
+	var $httpcode = 200;
+	var $httpdesc = "";
+	public function __construct($message="", $code = 0, Exception $previous = null) {
+		if ($this->httpdesc=="") {
+			$this->httpdesc = preg_replace("|([a-z])([A-Z])|",'$1 $2', str_replace("Exception","",get_class($this)));
+		}
+		parent::__construct($message, $code, $previous);
+	}
+}
+
+// 4xx
+class TooManyRequestsException extends HTTPException {
+	var $httpcode = 429;
+}
+
+class UnauthorizedException extends HTTPException {
+	var $httpcode = 401;
+}
+
+class ForbiddenException extends HTTPException {
+	var $httpcode = 403;
+}
+
+class NotFoundException extends HTTPException {
+	var $httpcode = 404;
+}
+
+class GoneException extends HTTPException {
+	var $httpcode = 410;
+}
+
+class MethodNotAllowedException extends HTTPException {
+	var $httpcode = 405;
+}
+
+class NonAcceptableException extends HTTPException {
+	var $httpcode = 406;
+}
+
+class LenghtRequiredException extends HTTPException {
+	var $httpcode = 411;
+}
+
+class PreconditionFailedException extends HTTPException {
+	var $httpcode = 412;
+}
+
+class UnsupportedMediaTypeException extends HTTPException {
+	var $httpcode = 415;
+}
+
+class ExpetationFailesException extends HTTPException {
+	var $httpcode = 417;
+}
+
+class ConflictException extends HTTPException {
+	var $httpcode = 409;
+}
+
+class UnprocessableEntityException extends HTTPException {
+	var $httpcode = 422;
+}
+
+class ImATeapotException extends HTTPException {
+	var $httpcode = 418;
+	var $httpdesc = "I'm A Teapot";
+}
+
+class BadRequestException extends HTTPException {
+	var $httpcode = 400;
+}
+
+// 5xx
+
+class ServiceUnavaiableException extends HTTPException {
+	var $httpcode = 503;
+}
+
+class BadGatewayException extends HTTPException {
+	var $httpcode = 502;
+}
+
+class GatewayTimeoutException extends HTTPException {
+	var $httpcode = 504;
+}
+
+class NotImplementedException extends HTTPException {
+	var $httpcode = 501;
+}
+
+class InternalServerErrorException extends HTTPException {
+	var $httpcode = 500;
+}
+
+
+