Fix documentation for sp-latex-point-after-backslash, add :unless

The :unless is added so that Smartparens will not expand ` and " when it is after a backslash.
Fix special case for " because it is a trigger
Switch to using let statement to only call function once
Merge pull request #278 from Sammidysam/latex-foreign-characters

Respect LaTeX Foreign Characters
[Issue #283] `navigate` action not set for mode-local pairs when they default to default set of actions.
Make the readme on default config cleaner (cf. Issue 280)
Update copyright notice to include year 2014
[Issue #285] Add a way to ignore certain sgml tags while searching for
closing.  Fix bug with backward motion and tag name being too long.
Auto-escape ' inside single-quoted strings.

Given the following text in a buffer, with | representing the cursor:

    'foo|bar'

Then pressing ' should give the following result:

    'foo\'|\'bar'

This is a part fix to Fuco1/smartparens#77.
Merge pull request #281 from Wilfred/master

Auto-escape ' inside single-quoted strings.
Fix docs
[Issue #292] Fix `sp-autoescape-string-quote-if-empty` not working, introduced in #281
When calling sp-insert-pair programatically, insert the opening pair before the testing is done
Add tests to cover #292
[Issue #292] Fix impossible autoescape in strings if sp-autoescape-string-quote-if-empty is set
Fix the default value of sp-autoskip-closing-pair
Strict delete routines should use 'navigate' action instead of 'insert'
(partially related to #231)
Better default config for lisp
Revert f37b048f and instead fix the `smartparens-strict-mode` init function.