Properly documented various functions of jTelegram in the wiki

[aaomidi]

The wiki is very sparse in information right now, this makes using the wrapper for the first time extremely difficult.

A proper wiki is important in allowing people to use all the various features we wrap around.

[Polve]

I can confirm I've a very hard time understanding how to use the libray.

Some pages are also out of date, using classes not existing any more on latest version.