Fix indexing mod items on windows filesystems

The keys are based on OS paths and it was only checking for / not / and
\.
This change skips the first character then matches items allowing for
both.
Allow for // inside valid JSON data

This modifies the regular expression to match for valid quoted strings
first before checking for single line comments.
URLs can be inside the JSON assets like .modinfo currently it will break
those files.

the lambda checks if m.group(1) exists (is a JSON data value) or it will
return '' for comments

References: http://stackoverflow.com/a/4577710
http://bugs.python.org/issue1519638#msg155982 so you can return a group
value even if that value could be blank
Allow capitalized species names in mods

Fixes the Vulpes species mod. The select statement use in name.lower()
so the kind should be indexed on .lower() also.
Index packed mods

The path for a packed mod looks to be ./nameofmod.pak
So treat it the same as a vanilla pak just filter out the ignored assets
(.db, ds_store etc)
Tested this with MedicalPotions mod
http://community.playstarbound.com/index.php?resources/medical-potions.927/
Merge pull request #58 from Septarius/moditemsindex

Fix indexing mod items on windows filesystems
Merge pull request #59 from Septarius/asseturldata

Allow for // inside valid JSON data
Change log file size, update config log in exceptions
Handle invalid JSON for mods files (skip it)
Fix loading icons with absolute key
Handle invalid JSON in pak files

I guess it could be possible?