rearrange and comment some functions

Move 2 functions further up syntastic.vim so that all public functions
are at the bottom - purely to be tidy.

Stick some comments on functions - most functions now have at least a
one liner explaining them.

Also, rename a variable in SyntasticHighlightErrors (since I had to look
at the log to figure out what it was).
add an option to disable error highlighting
fix a typo in the doc
Merge pull request #81 from millermedeiros/master

improve support for HTML5 attributes
javascript checker: make jshint 0.5.3 work
safe-guard against signs/balloons user settings when these features aren't available. see #113
Merge pull request #114 from millermedeiros/iss-sign

safe-guard against signs/balloons user settings
balloon_eval is already being checked at the top. see #114
Merge pull request #115 from millermedeiros/iss-sign

balloon_eval is already being checked at the top. see #114
add an option to SyntasticMake to specify defaults

Many of the syntax checkers were setting the 'bufnr' key for each
error manually and one was setting 'text' if it didnt exist too.

Add the 'defaults' option to SyntasticMake to set default values in the
returned error list - it only sets values if they are empty.
add applescript syntax_checker
0.2.1 - remove g:syntastic_applescript_tempfile. use tempname() instead.
Merge pull request #116 from zhaocai/master

add applescript syntax_checker
remove -nargs=0 from the :commands since this is the default
use custom highlight groups instead of tracking match ids

Use SyntasticWarning and SyntasticError highlight groups when calling
matchadd(). This makes it trivial to clear all of our highlights without
having to store IDs.

Stole this code from kevinw's pull request (#46)
echo the current error in the cmd win

This is largely taken from kevinw's pull request (#46).

Add the g:syntastic_echo_current_error option to deactivate the
functionality.
move the main autocmd into the syntastic augroup
fix a strange bug when echoing error messages

In the javascript:jshint checker the error messages are being returned
with a newline prefixed to the front. I have tried to fix this in the
errorformat - but I cant see anything that would cause it.

Im not sure if this is a one-off thing, but strip out all new lines here
just in case.
fix a minor issue when echoing the current error

Only clear the cmd window when it is displaying a message that we
echoed. Previously we were echoing a blank line every time the cursor
moved - this was clearing messages generated from other sources than
syntastic.
less checker: fix a syntax error

ironic?