doc: add and fix System Error properties

doc/api/errors.md

@@ -195,6 +195,8 @@ will either be instances of, or inherit from, the `Error` class.
 
 ### new Error(message)
 
+* `message` {String}
+
 Creates a new `Error` object and sets the `error.message` property to the
 provided text message. If an object is passed as `message`, the text message
 is generated by calling `message.toString()`. The `error.stack` property will
@@ -205,6 +207,9 @@ given by the property `Error.stackTraceLimit`, whichever is smaller.
 
 ### Error.captureStackTrace(targetObject[, constructorOpt])
 
+* `targetObject` {Object}
+* `constructorOpt` {Function}
+
 Creates a `.stack` property on `targetObject`, which when accessed returns
 a string representing the location in the code at which
 `Error.captureStackTrace()` was called.
@@ -238,6 +243,8 @@ new MyError().stack
 
 ### Error.stackTraceLimit
 
+* {Number}
+
 The `Error.stackTraceLimit` property specifies the number of stack frames
 collected by a stack trace (whether generated by `new Error().stack` or
 `Error.captureStackTrace(obj)`).
@@ -250,10 +257,13 @@ not capture any frames.
 
 #### error.message
 
-Returns the string description of error as set by calling `new Error(message)`.
+* {String}
+
+The `error.message` property is the string description of the error as set by calling `new Error(message)`.
 The `message` passed to the constructor will also appear in the first line of
 the stack trace of the `Error`, however changing this property after the
-`Error` object is created *may not* change the first line of the stack trace.
+`Error` object is created *may not* change the first line of the stack trace
+(for example, when `error.stack` is read before this property is changed).
 
 ```js
 const err = new Error('The message');
@@ -263,8 +273,10 @@ console.log(err.message);
 
 #### error.stack
 
-Returns a string describing the point in the code at which the `Error` was
-instantiated.
+* {String}
+
+The `error.stack` property is a string describing the point in the code at which
+the `Error` was instantiated.
 
 For example:
 
@@ -450,18 +462,47 @@ added properties.
 
 #### error.code
 
-Returns a string representing the error code, which is always `E` followed by
-a sequence of capital letters, and may be referenced in `man 2 intro`.
+* {String}
+
+The `error.code` property is a string representing the error code, which is always
+`E` followed by a sequence of capital letters.
 
 #### error.errno
 
-Returns a number corresponding to the **negated** error code, which may be
-referenced in `man 2 intro`. For example, an `ENOENT` error has an `errno` of
-`-2` because the error code for `ENOENT` is `2`.
+* {String | Number}
+
+The `error.errno` property is a number or a string.
+The number is a **negative** value which corresponds to the error code defined in
+[`libuv Error handling`]. See uv-errno.h header file (`deps/uv/include/uv-errno.h` in
+the Node.js source tree) for details.
+In case of a string, it is the same as `error.code`.
 
 #### error.syscall
 
-Returns a string describing the [syscall][] that failed.
+* {String}
+
+The `error.syscall` property is a string describing the [syscall][] that failed.
+
+#### error.path
+
+* {String}
+
+When present (e.g. in `fs` or `child_process`), the `error.path` property is a string
+containing a relevant invalid pathname.
+
+#### error.address
+
+* {String}
+
+When present (e.g. in `net` or `dgram`), the `error.address` property is a string
+describing the address to which the connection failed.
+
+#### error.port
+
+* {Number}
+
+When present (e.g. in `net` or `dgram`), the `error.port` property is a number representing
+the connection's port that is not available.
 
 ### Common System Errors
 
@@ -528,6 +569,7 @@ found [here][online].
 [`fs`]: fs.html
 [`http`]: http.html
 [`https`]: https.html
+[`libuv Error handling`]: http://docs.libuv.org/en/v1.x/errors.html
 [`net`]: net.html
 [`process.on('uncaughtException')`]: process.html#process_event_uncaughtexception
 [domains]: domain.html