This new keyword allows to add all the packages to the <layer>-packages
even when a package is not toggled on by a given layer variable.
This fixes an issue of the layer system where we had to choose between
discoverability (ie. the list of package in helm or ivy with SPC h SPC)
and installation of package (because any package listed in the variable
<layer>-packages were installed).
Key bindings should not be choosen given a package name, some helm
key bindings are under `SPC h` which are corrected the following way:
SPC h l for helm-resume to SPC r l (resume last completion)
SPC s l for last-search to SPC r s (resume search) (SPC s l is still
available)
SPC h L for helm-locate-library to SPC s L
Resolve#4592
`SPC j j` is now for avy-goto-char (SPC SPC in 0.105)
`SPC j J` is for avy-goto-char-2
`SPC j s` is for splitting strings or sexps
`SPC j S` is for splitting strings of sexps, insert new line and indent
`SPC j n` is to split line at point, insert new line and indent