created variable org-gcal-header-alist

(setq org-gcal-header-alist '(("[email protected]" .
      "#+CATEGORY: personal\n#+ARCHIVE: archive/personal.org")))

Previously, private events were not emitted correctly which would cause the event prior to the private event to have multiple times.

this is to address issues like myuhe#29 when event descriptions that include
'*' can break gcal synchronization

It's an alist, customize it as such.  With this patch I can customize
and then org-gcal-fetch (without it I cannot).

JSON text exchanged between systems that are not part of a closed
ecosystem MUST be encoded using UTF-8. [1]

[1] The JavaScript Object Notation (JSON) Data Interchange Format
    https://tools.ietf.org/html/rfc8259

Merges pr60 from upstream myuhe#60

org-archive-subtree messes the kill-ring.  Wrapping it in a let binding
creating a copy of kill-ring and we restore the kill-ring after the messup.

Update documentation

Avoid kill ring messup

* alert.el already manages a default emacs logo. If user wants a
different one, set the new `org-gcal-logo-file' variable to the path
of the logo.

* removed `org-gcal-logo' variable

Simplify notification logo setup

Documentation for myuhe PRs

Detect appropriate calendar id from current buffer when requesting
post or delete an event.  Raise user-error if no calendar id is found.

Support multiple calendar.

Added proper error message and readme documentation about it.

Clarified parse error a bit.

remove unused variables

add autoloads

Use defcustom to define org-gcal-header-alist and add docstring

Fix formatting and replace tabs with spaces

Fix some parens corrupted in e93ed22 (PR myuhe#16)

This makes the code work with indirect buffers as well as normal buffers. 
Working with indirect buffers make org-gcal-post-at-point work with capture buffers, and make the capture hook work.

Makes org-gcal work with indirect buffers

 Fix issue where multi-line locations led to duplicate calendar entries