This changes the return type of at least the following functions from IO Bool to IO (Either XmppFailure ())
* sendIQ
* sendIQ'
* answerIQ
* sendMessage
* sendPresence
IQResponseTimeout does not model an XMPP type but is instead an implementation specific signal that a user-set timeout has occured. Removing it keeps our representation closer to the defined protocol.
add IQSendError to keep the result of sendIQ' clear
stanza handlers used to return a Boolean value to indicate whether stanza processing should continue. Now the return lists of stanzas instead. This facilitates plugins that transform stranzas (e.g. encryption)
Stanza send functionality now directly sends the stanzas over the wire and returns appropriate notification whether the sent succeeded (as far as we can tell)
The way I understand it, the `Show' and `Read' instances are for `String' representations that can be Haskell code. A proper `Show' instance of `Jid' would produce something like `Jid (Just "test") "example.com" Nothing'. A proper `Read' instance of `Jid' would parse something like that `String' value, and would stop parsing when completed.
This patch automatically derives the `Show' instance from `Jid'. It also uses the previous `Show' instance to create a pretty printer, `jidToText'. It also provides a (trivial) `jidToTexts'. As an automatically derived `Read' instance could be used to create invalid `Jid' values and affect the correctness of applications using Pontarius XMPP, such a derivation has not been included. This required some changes in the `Jid' marshalling code, which assumed a `Read' instance.
Since we provide `jidFromText', I'm assuming that no-one needs a `Read' instance of `Jid'.
Fixes#24.
Move the functionality from Network.Xmpp.IM.Message and *.Presence to Network.Xmpp.Stanza since it is not specific to RFC 6121.
Implement presence functionality of RFC 6121
Fix hslint errors and warning
Philipp Balzarek
Michael Snoyman
Jon Kristensen