single line JS comments are transformed into /**/

// comments are hazardous when compiling content.
ESCAPED_QUOTE is now a token, to actually ensure escaped quotes remain
Revert "single line JS comments are transformed into /**/"

Don't know why I thought this was important

This reverts commit c095ae33993e50a8a8b72be029335e753235b286.

Conflicts:
	package.json
AT_COLON could not be escaped properly
<text> can be escaped using explicit expression
// comments are now a token + tests

This allows them to be separately consumed in markup vs block,
specifically during //@batch calls. This means helpers and batch
compilation can be handled more simply.
vash.compileHelper now accepts multiple helpers.

This is extremely similar to vash.batch, and will be refactored.
vash(1) has --helper, which will batch-compile
a self-closing tag should not always exit curr ast

If the parent is BLK, a self closing tag should only exit if the current
node does not have a tag name. This prevents the self-closing tag from
closing the current markup block, switching to BLK, and then switching
back to the closing tag. It also prevents a self-closing tag closing the
curent markup block, and then subsequent markup content getting treated
as BLK:

	@if(true){ <a>Hello <br /> world!</a> }

Was throwing an error, trying to use `world` as BLK.
refactor vash.build, vash.compileHelper

the logic is practically the same.
vash.batch is now vash.compileBatch

vash.batch points at vash.compileBatch

API consistency:

	vash.compile
	vash.compileHelper
	vash.compileBatch
single line comments are no longer special

It's not worth keeping track of them, as they are easily confused with
URLS without more advanced parsing.
backslashes in content were not being escaped properly
vash(1) --helpers <file>

A file can be passed in, and thus when paired with --render, can enable
helpers via command line. A complex example:

	cat myTpl.vash | bin/vash --render --helpers \
		<(cat helpers/* | bin/vash --helper)

This example grabs all the files in the helpers directory, compiles them
as helpers, and then passes them as a temporary named pipe into another
call to vash(1) that is rendering myTpl.vash.
compiled helpers can begin with newlines
backslashes should only be escaped for markup

In EXP or BLK, assume the developer knows what they're doing. If they
specify an explicit backslash, it's probably for a good reason and
should not be double escaped.
Unified non-void and void html tags (self-closing)

A void html element, such as <br />, previously could not contain
something like <br @(what ? sure : ok) />. This was because the logic
for self-closing tags was separate from the much more complex
HTML_TAG_OPEN lexing. Now an HTML_TAG_VOID_OPEN is checked for first,
and if found, the ast is marked via `tagVoid`.
Buffer#lastIndexOf, Buffer#indexOf can take regex
html.options within template === render options

__vopts / html.options is now always at least an object.

This is mainly to allow a helper to hook into the `onRenderEnd` callback
to do any cleanup/finalizing it may want.
vash.helpers.trim in optional helpers