bug report instructions (#248)

Author: geoffroyleconte

README.md

@@ -122,3 +122,10 @@ full(opA[:,1]) # nx1 matrix
 * [MUMPS.jl](https://github.com/JuliaSmoothOptimizers/MUMPS.jl) features a full
   distributed-memory factorization operator that may be used to represent the
   preconditioner in, e.g., constraint-preconditioned Krylov methods.
+
+## Bug reports and discussions
+
+If you think you found a bug, feel free to open an [issue](https://github.com/JuliaSmoothOptimizers/LinearOperators.jl/issues).
+Focused suggestions and requests can also be opened as issues. Before opening a pull request, start an issue or a discussion on the topic, please.
+
+If you want to ask a question not suited for a bug report, feel free to start a discussion [here](https://github.com/JuliaSmoothOptimizers/Organization/discussions). This forum is for general discussion about this repository and the [JuliaSmoothOptimizers](https://github.com/JuliaSmoothOptimizers) organization, so questions about any of our packages are welcome.

docs/src/index.md

@@ -109,3 +109,10 @@ Matrix(opA[:,1])
 ```julia
 julia> Pkg.test("LinearOperators")
 ```
+
+## Bug reports and discussions
+
+If you think you found a bug, feel free to open an [issue](https://github.com/JuliaSmoothOptimizers/LinearOperators.jl/issues).
+Focused suggestions and requests can also be opened as issues. Before opening a pull request, start an issue or a discussion on the topic, please.
+
+If you want to ask a question not suited for a bug report, feel free to start a discussion [here](https://github.com/JuliaSmoothOptimizers/Organization/discussions). This forum is for general discussion about this repository and the [JuliaSmoothOptimizers](https://github.com/JuliaSmoothOptimizers) organization, so questions about any of our packages are welcome.