Add optional argument for quantity to get_note_list()

As per changes to Simplenote.py:
https://github.com/i5m/simplenote.py/commit/ef3b4ee

===========

Adds an optional argument allowing the user to specify the exact
number of notes to return in the list. If the argument is not set
by the user then it is assumed to be "infinite", or "all" notes.

If the quantity is less than the NOTE_FETCH_LENGTH (currently
specified as 20) then a call is made for the exact number of notes
required.

Otherwise, the correct quantity is determined in the while loop that
looks at the "mark" key set by Simplenote."

===========
Merge branch 'release/v0.3.1' into develop
autoload; inspired in @b862ec30e3d
move plugin to autoload
create interface in plugin folder
Merge branch 'feature/autoload' into develop
Merge remote-tracking branch 'juanpabloaj/autoload' into develop

Conflicts:
	autoload/simplenote.vim
	plugin/simplenote.vim
remove loaded guard as it prevents loading autoload part
bump version to v0.4.0
Merge branch 'release/v0.4.0'
Merge branch 'release/v0.4.0' into develop
Allow vertical splitting of scratch buffer
make pretty formatting for note list
bugfix: make only the file list nowrap
Merge branch 'develop' into develop-limit-list

Conflicts:
	plugin/simplenote.vim

Merging in upstream changes. Because of change to autoload, had to
change the way the option parameter for the limit list functionality
was supplied.
update to simplenote.py v0.2.0
don't add notes to list if status suggests an error

this fixes #31 in the sense that no malformed note objects should be in the
list anymore. However this does not mean that notes whose fetch resulted in an
error are refetched. This would slow down the already slow fetching process
further more and most likely the important notes might be fetched without
problems. So this does not make a lot of sense at the moment. Retrying the
list fetch with `:Simplenote -l` in case the desired note is not there is a
much more sensible solution I think.
Merge branch 'master' into develop
Merge branch 'develop-limit-list' of https://github.com/atomicules/simplenote.vim into develop
Merge branch 'master' of https://github.com/myw/simplenote.vim into develop