Update postcode required defaults
Update United Kingdom address format
Fixes #30 "Undefined index: cart" error
Reduce file_get_contents warnings in cache
Spelling and unit corrections
Admin validation correction
Removed contribution spelling guideline

Removed readme/contribution spelling guideline as OpenCart source is
already inconsistent with British/American English spelling use.

https://github.com/opencart-ce/opencart-ce/issues/33
Add redirect to secure pages

Pages that can be indexed use code 301.
Closes #32 file size prefix standardization

http://en.wikipedia.org/wiki/Binary_prefix