Update spanish translation
Various doc fixes.
Merge pull request #443 from LuqueDaniel/update-es

Update spanish translation
Revert take_execution_state to the 6.17 version.

This is intended to fix problems caused by the changes outside of
screens.
sl2: Do not take state from predicted displayables or transforms.

If the parameters to a displayable or transform change between
when a screen is predicted and when it is shown, it means that
the prediction was incorrect.

We now discard the incorrect prediction state, instead of allowing it
to influence the screen.

See: http://lemmasoft.renai.us/forums/ucp.php?i=pm&mode=view&f=0&p=144880
See: http://lemmasoft.renai.us/forums/viewtopic.php?p=338394#p338394
Error out if the base directory doesn't exist.
Do not use the game-local save directory on Android.

Relevant to #441.
Test that save directories are writable on Android before using them.

Relevant to #441.
Use RENPY_AUTO_LOAD to override config.auto_load.

This provides an easy way to force a save load for development
purposes.
Transpose grids as we render the grid.

Before this patch, we would transpose grids once, which caused a
problem where a reused grid would only be transposed once.

See: https://mail.google.com/mail/u/0/#inbox/1484b917bff1005b (Private)
Fix formatting of "could not find return label".
Update properties in Transform.default_function.

This preserves non-ATL transform behavior in the face of taking
state and execution state.

Fixes #445.
sl2: Implement the "use <screen> id <id>" syntax.

Where sl1 used structural equality to transfer state between
screens sharing the same tag, sl2 can't do that. (Doing so would
require maintaining _name, which is expensive.)

Instead, we allow uses of screens to include an id property,
which explcitly specifies equality of used screens.
Document use statement changes.
Allow a transform to have both a function and arguments.

This fixes a regression of the 6.17 behavior.

See: Jake's battle engine.
Ignore time spent not scrolling when edge scrolling.

This prevents big jumps from occuring when the mouse leaves one side
of the window, and re-enters on another side of the window.

Fixes #431.
When a used screen takes parameters, persist its scope across interactions.

This makes sense for the new behavior of screens with parameters,
and is useful.

Fixes #194.