Set default match for org-dotemacs-load-file and update comments

Altered items:
org-dotemacs-load-file
Update TODO
New function org-dotemacs-load-blocks

org-dotemacs-load-blocks loads the code blocks directly from the org
file instead of saving them to a file first. It also does error checking
and reporting.

Altered items:
org-dotemacs-load-blocks
Changes to org-dotemacs-load-file

Now it org-dotemacs-load-file uses the org-dotemacs-load-blocks function

Altered items:
org-dotemacs-load-file
Remove org-dotemacs-extract-code function

No longer needed.

Altered items:
org-dotemacs-extract-code, org-dotemacs-load-file
Added string-split, added retry arg to org-dotemacs-load-blocks

Added retry arg org-dotemacs-load-blocks and altered behaviour
so that failed blocks will be retried. Also failed blocks divided
into blocks with errors and blocks with unmet dependencies.
Added string-split function (needed for checking dependencies).

Altered items:
string-split, org-dotemacs-load-file, org-dotemacs-load-blocks