Fix link to meta in guideline (#442)

docs/src/guidelines.md

@@ -29,7 +29,7 @@ function MyModel()
 end
 ```
 More information can be passed to `NLPModelMeta`.
-See the full list [here](https://github.com/JuliaSmoothOptimizers/NLPModels.jl/blob/main/src/nlp_types.jl#L28).
+See the full list [here](https://github.com/JuliaSmoothOptimizers/NLPModels.jl/blob/main/src/nlp/meta.jl#L32).
 The essential fields are
 - `x0`: Starting point (defaults to `zeros`)
 - `lvar`, `uvar`: Bounds on the variables (default to `(-∞,∞)`)
@@ -143,4 +143,4 @@ Furthermore, the `show` method has to be updated with the correct direction of `
 ## [Advanced tests](@id advanced-tests)
 
 We have created the package [NLPModelsTest.jl](https://github.com/JuliaSmoothOptimizers/NLPModelsTest.jl) which defines test functions and problems.
-To make sure that your model is robust, we recommend using that package.
+To make sure that your model is robust, we recommend using that package.