Streamlined pwsz loading from Linux shells

Get-Path updated to support @ notation.
MyConfig class updated to resolve Paths before testing.
MyScript class will look recursivley - this might need to change again.
config.files.json updated to support shell-loading-snippets
shell-loading-snippets added, with single line of code to inject into
startup shell scripts (.zshrc, .bashrc, .shrc)

base/src/config.files.json

@@ -16,6 +16,7 @@
   "vi": "~/.virc",
   "sz-local-rc": "~/.sz.local.sh",
   "zshrc": "~/.zshrc",
+  "shrc": "~/.shrc",
   "ansible": [
     "/etc/ansible/ansible.cfg",
     "/opt/ansible/ansible.cfg",
@@ -26,9 +27,15 @@
     "~/.vimrc",
     "~/.vim/vimrc"
   ],
+  "sz-shrc": [
+    "#shrc",
+    "@shell-loading-snippets/bash",
+    "@shell-loading-snippets/sh"
+  ],
   "sz-zshrc": [
     "~/.sz.zshrc.sh",
-    "#zshrc"
+    "#zshrc",
+    "@shell-loading-snippets/zsh"
   ],
   "tmux": [
     "~/.tmux.conf",