Add basic XDG compliant sh architecture

The only file left in $HOME is .zshenv, which sets up zsh to source everything from XDG_CONFIG_HOME/zsh.
Shell files are split into sh and zsh directories, for global assignments (which should be posix compliant, work on any posix shell) like environemnt variables, xdg vars, and global aliases. zsh contains zsh specific customization (prompt customization, plugin loading, zsh completions).

Zsh initialization will pull from sh directory first, loading the respective mirror to its startup file (`.zprofile` loads `sh/profile` and `profile.d/*`, `.zshenv` loads `sh/env` and `sh/env.d/*` and `zsh/env.d/*`, `.zshrc` loads `sh/alias`, `sh/alias.d/*` and `zsh/alias.d/*`)

Once all is done, it will have loaded both global variables, aliases and settings, and zsh-only specifications. Other stow modules, if they want to add shell functionality, can include their aliases and functions in one of the above directories to automatically be picked up by zsh.

.gitignore

@@ -1,50 +1,6 @@
-*/.netrwhist
-**/gopass-logo-small.png
-
-# Created by https://www.gitignore.io/api/vim,linux
-# Edit at https://www.gitignore.io/?templates=vim,linux
-
-### Linux ###
-*~
-
-# temporary files which can be created if a process still has a handle open of a deleted file
-.fuse_hidden*
-
-# KDE directory preferences
-.directory
-
-# Linux trash folder which might appear on any partition or disk
-.Trash-*
-
-# .nfs files are created when an open file is removed but is still being accessed
-.nfs*
-
-### Vim ###
-# Swap
-[._]*.s[a-v][a-z]
-[._]*.sw[a-p]
-[._]s[a-rt-v][a-z]
-[._]ss[a-gi-z]
-[._]sw[a-p]
-
-# Session
-Session.vim
-Sessionx.vim
-
-# Temporary
-.netrwhist
-
-# Auto-generated tag files
-tags
-
-# Persistent undo
-[._]*.un~
-
-# Coc configuration directory
-.vim
-
-# End of https://www.gitignore.io/api/vim,linux
-
+# no idea why gopass adds this image to config path
+gopass-logo-small.png
+#
 # Ignore dynamic colorschemes set by styler
 colorscheme.vim
 colorscheme