`Base.findmin(s1, s2, dist::Partial)`

[ericphanson]

Hi and thanks for the great package!

I found the following snippet (modified from (dist::Partial)(s1, s2)) useful and I was wondering if it would be worth adding to StringDistances? I could make a PR if so.

julia> function Base.findmin(s1, s2, dist::Partial; max_dist = 1.0)
    s1, s2 = StringDistances.reorder(s1, s2)
    len1, len2 = length(s1), length(s2)
    len1 == len2 && return dist.dist(s1, s2, max_dist), firstindex(s2):lastindex(s2)
    len1 == 0 && return max_dist+1, 1:0
    out = max_dist+1
    out_idx = 0
    for (i, x) in enumerate(qgrams(s2, len1))
        curr = dist.dist(s1, x, max_dist)
        out_idx = ifelse(curr < out, i, out_idx)
        out = min(out, curr)
        max_dist = min(out, max_dist)
    end
    return out, nextind(s2, 0, out_idx):nextind(s2, 0, out_idx+len1-1)
end

julia>  findmin("βabc", "βadcacαaXXcαγ", Partial(DamerauLevenshtein()))
(0.25, 1:5)

julia> "βadcacαaXXcαγ"[1:5]
"βadc"

Also, I am new to working with unicode strings, so it's possible I haven't used nextind correctly.