Create log_dir path directories recursively

This change will create the custom log folder and its parents, if needed, in the case of using absolute paths too.
Update urlrequest.py

Added '''and the response
to the request will be accessible as the parameter called "result" on the callback
function of the on_success event.'''.
Add largs in config register func. + PEP8 fix.
include inner traceback in BuilderException
doc: reorganized packaging doc order (OS grouped together)
doc: corrected heading to be subheading
doc: added indexing header for "targetting_adroid"
Remove strange chars.
Merge pull request #2235 from kived/builder-exceptions

include inner traceback in BuilderException
doc: clarified "Scatter.apply_transform"
fix error message about number of stencils thanks zeddy
doc: hid "Scatter." in ref link
doc: added note on not setting the "Scatter.transform" matrix directly
Merge branch 'master' of git://github.com/kivy/kivy
Add note about twisted on iOS
Merge pull request #2237 from matham/joy

Remove strange chars.
Merge pull request #2240 from bionoid/twistednote

Add note about twisted on iOS
doc: corrections to 'Scatter.transform' behaviour
Fix incorrect attr links in uix/settings
Merge pull request #2241 from bionoid/settingsdocs

Fix incorrect attr links in uix/settings