Initial set of docs

Hi Susan,

I've just committed the initial versions of the docs you sent
recently, so we've got something in git to work from. I made a number
of quick changes:

- Added an index page for them (object-dialogs.rst), and linked it
from the main index.

- Fixed a number of references to images.

- Fixed a minor markup issue.

Can you please look into the following issues?

1) We're just having a single doc page for each dialogue, so let's
drop the "create_" prefix from the rst and png files.

2) There are a couple of images missing:

/Users/dpage/git/pgadmin4/docs/en_US/create_event_trigger.rst:66:
WARNING: image file not readable:
images/create_event_trigger_sql_example.png"FIXME"

/Users/dpage/git/pgadmin4/docs/en_US/create_tablespace.rst:77:
WARNING: image file not readable:
images/create_tablespace_sql_example.png

3) You include links to the PG docs in a few places. I think we should
remove that because a) it's hard coded to a single version of
PostgreSQL, and b) each dialog now has a button on it that will take
you to the appropriate create/alter documentation page for the version
of PG or PPAS that you're currently using.

4) I know you had some technical feedback on the docs that has yet to
be incorporated. Please send patches for that when you're able.

5) Feel free to update the index page etc. with better wording!

Finally - we need a button on each dialog to open the appropriate help
page. I'll work on that.

Thanks, Dave.


--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

EnterpriseDB UK: http://www.enterprisedb.com
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