Refactor .zshrc

- Split login stuff into .profile
- Symlink .profile to .zprofile since zsh only loads the latter
- Drop QPA_PLATFORMTHEME and see what breaks
- Make bat my pager where I have it, most where I don't
- Drop the OS-detection stuff for ls, use exa if I have it
- Drop a couple old aliases

.profile

@@ -0,0 +1,24 @@
+export LANG=en_US.UTF-8
+
+# Start keychain only on my personal system
+if [ -z "$SSH_CLIENT" ] && [ -z "$SSH_TTY" ]; then
+    eval `keychain --eval id_ed25519`
+fi
+
+# These are pretty safe to assume exist
+export PATH=~/bin:$PATH
+export EDITOR=vim
+export VISUAL=$EDITOR
+
+# Figure out my pager; these don't necessarily exist
+if [ -e /usr/bin/bat ]; then
+    export PAGER="bat --plain"
+elif [ -e /usr/bin/most ]; then
+	export PAGER=most
+fi
+
+# Set shell history values
+# We use one history for any shell, which might bite us one day?
+export HISTFILE=~/.history
+export HISTSIZE=10000
+export SAVEHIST=10000