outputTemplate: support

[nblumhardt]

Although this sink can't use the built-in output template formatting directly, it should still be possible to accept and control output using a regular output template, e.g.:

WriteTo.BrowserConsole(outptTemplate: "{Message} {Properties}{NewLine}{Exception}")

The regular Console sink does something similar to support theming.

[zetroot]

Looks great feature, i would like to participate in this feature.
I am quite new to Serilog, so i have several questions. Could you clarify the task?
As far as i can understand, words in curly brackets are some kind of key-words.
Ok, Message stands for logging message, i understand,
NewLine - stands for Environment.NewLine property, ok.
Exception - should be added if there is an exception passed to log method.
What are Properties?

[zetroot]

Oh, i see, Properties stands for LogEvent._properties member. Now it seems clearer for me.
What about other kinds of keywords?

[nblumhardt]

Hi @zetroot! https://github.com/serilog/serilog/wiki/Formatting-Output#formatting-plain-text has the info you need, I think.

[zetroot]

Thank you @nblumhardt !
Now it became much clearer for me

[nblumhardt]

Merged in #13 🎉