Index of pending issues spread at different repositories

[amartinhuertas]

List of issues spread around different repositories which must be taken into account for the development of this repo:

More strategic

• GMG solver pending tasks. [DONE]
• Brainstorming about next steps

Less strategic/more detailed

• Testing performance of matrix-free implementations
• Optimizing single-core performance for sum-factorization
• Implementing even-odd decomposition