Fixed onPreStart, spaces in friend filter, and backspacing in filter

-onPreStart bug:
  onPreStart() was called before the fsOptions were filled in with
defaults causing an error whenever fSelector was used without
specifying onPreStart()

Uncaught TypeError: Object #<Object> has no method 'onPreStart'

-Spaces in friend filter bug:
  Everytime you put a space in the friend filter box, the css attribute
selector wouldn't work because the spaces were being replaced by '+'s.
I believe some symbols just don't work in those selectors?  I tried +
and &.  I just ended up using a 0 to replace spaces by, but if
something that's not a number works that would be great.

Example error:
Uncaught Error: Syntax error, unrecognized expression: #fs-user-list
.fs-fullname[value*=jessica+c]

-Backspacing in friend filter bug:
  If you filtered friends by some string (ex: "jes"), but then
backspaced so that you had nothing in the filter box, no friends would
show up because the attribute selector value*=search_text was still
being performed, but search_text was an empty string
Merge pull request #13 from smilli/friend-filter-bug-fix

Fixed onPreStart, spaces in friend filter, and backspacing in filter

Thanks @smilli 

It's time for retirement for this repo. I don't have much time and passion to update this plugin.