Readme: Add reference to UnitfulParsableString.jl

README.md

@@ -31,6 +31,7 @@ mathematical operations and collections that are found in Julia base.
 
 - [UnitfulEquivalences.jl](https://github.com/sostock/UnitfulEquivalences.jl): Enables conversion between equivalent quantities of different dimensions, e.g. between energy and wavelength of a photon.
 - [UnitfulLatexify.jl](https://github.com/gustaphe/UnitfulLatexify.jl): Pretty print units and quantities in LaTeX format.
+- [UnitfulParsableString.jl](https://github.com/michikawa07/UnitfulParsableString.jl): add method `Unitful.string` to convert `Quantity` (or some type) to parsable `String`.
 - [UnitfulBuckinghamPi.jl](https://github.com/rmsrosa/UnitfulBuckinghamPi.jl): Solves for the adimensional Pi groups in a list of Unitful parameters, according to the Buckingham-Pi Theorem.
 - [NaturallyUnitful.jl](https://github.com/MasonProtter/NaturallyUnitful.jl): Convert to and from natural units in physics.
 - [UnitfulChainRules.jl](https://github.com/SBuercklin/UnitfulChainRules.jl): Enables use of Unitful quantities with [ChainRules.jl](https://github.com/JuliaDiff/ChainRules.jl)-compatible autodifferentiation systems.