allow multiple at chars at a time

[panzhangwang]

Quick question. Does it allow multiple chars at a time like at.js? Say, whatever '@' or ':' is there, pop up a suggestion box?

[fritx]

@panzhangwang oh seems it is not supported yet.
Will try to fix, otherwise, PR is welcome.

vue-at/src/At.vue

Lines 204 to 206 in 3cc035f

	const index = text.lastIndexOf(at)
	if (index < 0) show = false
	const prev = text[index - 1]

Currently the :at prop accepts only a string, not a pattern or an array.

[4ver]

See #17

[fritx]

Thanks to @4ver, now we can have multiple at-chars at the same time.
This is fixed.

<at :ats="['@', '＠', '~', ':', 'xx']"></at>