Add function signature within its docstring

[amontoison]

#207

[coveralls]

Coverage remained the same at 97.389% when pulling badf31a on amontoison:docs into cd6b051 on JuliaSmoothOptimizers:master.

[dpo]

:-(
what about automatically-generated signatures in the docstring? The advantage is that they stay in sync with the actual function signature.

[codecov]

Codecov Report

Merging #208 into master will decrease coverage by 0.06%.
The diff coverage is 98.78%.

@@            Coverage Diff             @@
##           master     #208      +/-   ##
==========================================
- Coverage   97.42%   97.36%   -0.07%     
==========================================
  Files          30       29       -1     
  Lines        3229     3193      -36     
==========================================
- Hits         3146     3109      -37     
- Misses         83       84       +1     

Impacted Files	Coverage Δ
src/Krylov.jl	100.00% <ø> (ø)
src/bilq.jl	100.00% <ø> (ø)
src/bilqr.jl	100.00% <ø> (ø)
src/cg.jl	100.00% <ø> (ø)
src/cg_lanczos.jl	100.00% <ø> (ø)
src/cgls.jl	100.00% <ø> (ø)
src/cgne.jl	100.00% <ø> (ø)
src/cgs.jl	100.00% <ø> (ø)
src/cr.jl	57.23% <ø> (-0.27%)	⬇️
src/craig.jl	96.72% <ø> (-0.03%)	⬇️
... and 46 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update cd6b051...badf31a. Read the comment docs.

[amontoison]

We don't have any news from JuliaDocs/DocStringExtensions.jl for our problem. Should we add signatures in the docstring by hand for the moment? It will be better than nothing.

[dpo]

Sure. DocstringExtensions is a bit disappointing... :-(

[amontoison]

It's not fun to do, but It should help a lot the users of Krylov.jl.

[dpo]

Indeed! Thank you!