Add support for Kotlin @Deprecated annotation

[alshan]

I deprecated symbol "lets_plot" in favor of "letsPlot":

@Deprecated("", ReplaceWith("letsPlot(data, mapping)"))
fun lets_plot(data: Map<*, *>? = null, mapping: GenericAesMapping.() -> Unit = {}) = letsPlot(data, mapping)

In IDEA user can see the deprecated symbol and can choose to auto-fix:

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In Jupyter notebook user can not tell a deprecated symbol from the new one (and most likely there is no auto-fix provided):

[ileasile]

There is really no autofix and crossed completion variants, but there should be warnings:

Do you have them?

[alshan]

See them but not always - see screenshot for example.