Update README.md

Author: MikeInnes

README.md

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 # LNR
 
-[![Build Status](https://travis-ci.org/one-more-minute/LNR.jl.svg?branch=master)](https://travis-ci.org/one-more-minute/LNR.jl)
+LNR.jl implements a `LineNumberingReader` type which transparently wraps any other reader (`::IO`). It's intended for working with hand written text where line and column information is significant, and provides functions for working with this information.
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+`LineNumberingReader`s can be created with either an IO object or a string as a parameter.
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+The `Cursor` type, which has the `line` and `column` fields, represents a position between two characters (and not the character itself). So `Cursor(n, m)` represents the position just before the `m`th character on line `n`. Comparisons are supported.
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+The `cursor` function gives the current position in the stream as a cursor. `seek` can be called as usual, but with a `Cursor` instead of an integer, to set the reader at any position in the file.
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+Other than that, standard IO functions are wrapped, so you can use a line reader as you would any other stream.