Refactor Project API to reflect changes upstream

projectile-project-root no longer returns `default-directory` if not in
a project (it returns nil). As such, doom-project-* functions (and their
uses) have been refactored.

+ doom-project-p & doom-project-root are aliases for
  projectile-project-p & projectile-project-root.
+ doom-project-{p,root,name,expand} now has a DIR argument (for
  consistency, since projectile-project-name and
  projectile-project-expand do not).
+ The nocache parameter is no longer necessary, as projectile's caching
  behavior is now more sane.
+ Removed some projectile advice/hacks that are no longer necessary.
+ Updated unit tests

modules/ui/modeline/config.el

@@ -314,7 +314,7 @@ e.g. ~/w/project/src/lib/file.c
 Meant for `+modeline-buffer-path-function'."
   (pcase-let
       ((`(,root-parent ,root ,dir, file)
-        (shrink-path-file-mixed (doom-project-root)
+        (shrink-path-file-mixed (or (doom-project-root) default-directory)
                                 (file-name-directory buffer-file-name)
                                 buffer-file-name)))
     (list (cons root-parent 'font-lock-comment-face)

modules/ui/neotree/autoload.el

@@ -8,7 +8,7 @@
 (defun +neotree/open ()
   "Open the neotree window in the current project."
   (interactive)
-  (let ((project-root (doom-project-root 'nocache)))
+  (let ((project-root (doom-project-root)))
     (require 'neotree)
     (if (neo-global--window-exists-p)
         (neotree-hide)
@@ -19,7 +19,7 @@
   "Open the neotree window in the current project, and find the current file."
   (interactive)
   (let ((path buffer-file-name)
-        (project-root (doom-project-root 'nocache)))
+        (project-root (doom-project-root)))
     (require 'neotree)
     (cond ((and (neo-global--window-exists-p)
                 (get-buffer-window neo-buffer-name t))

modules/ui/treemacs/autoload.el

@@ -10,8 +10,8 @@
       (treemacs-do-remove-project-from-workspace project))
     (with-current-buffer origin-buffer
       (treemacs-do-add-project-to-workspace
-       (treemacs--canonical-path (doom-project-root 'nocache))
-       (doom-project-name 'nocache))
+       (treemacs--canonical-path (doom-project-root))
+       (doom-project-name))
       (setq treemacs--ready-to-follow t)
       (when (or treemacs-follow-after-init treemacs-follow-mode)
         (treemacs--follow)))))