Change install script to be more portable and expansion issues on files with spaces

[kepet19]

replace '~' with $HOME, because Tilda sometimes does not expand in double quotes. I put double quotes around the input augment to the command. If the variable should have a space in it would have taking it as there was two augments to the command.

for esay checking if the script hold true to either posix or a specific shell edit the shebang !# to /bin/sh for posix shell or /bin/bash for bash shell. # apt install shellcheck I have this specific vim remap.

noremap <leader>s :!clear && shellcheck %<CR>