fix typo; fix integer overflow for 32bit systems

[MrEcco]

Got this error while building your gotemplate project for linux/arm/v6 and linux/arm/v7. This looks like an obvious miss of support of 32bit -based systems. I bet you skip such systems because of various places where it might not work, but if this PR doesn't hurt then it might be a small stop toward it.
I'm not familiar with where you use this library, so cannot guarantee it doesn't break something :)

[MrEcco]

Look here:

multilogger/level.go

Line 43 in 1ba5406

if levelNum == int(DisabledLevel) {

. You do int(math.MaxUint32) and for 32-bit size pointers it collapses.

[MrEcco]

Tried to build my Dockerfile like this:

ARG GOTEMPLATE_VERSION=3.12.0
RUN cd /tmp                                  && \
    apk add --no-cache                          \
        git                                     \
        go                                   && \
    git config --global advice.detachedHead false && \
    git clone --depth 1 --branch v${GOTEMPLATE_VERSION} https://github.com/coveooss/gotemplate && \
    cd gotemplate                            && \
    go build -ldflags "-s -w" .              && \
    strip -g -S -d --strip-debug ./gotemplate

# command
docker buildx build --progress plain --platform linux/arm/v7 .
docker buildx build --progress plain --platform linux/arm/v6 .

Got this error:

......
9.558 go: downloading github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da
9.564 go: downloading github.com/kevinburke/ssh_config v1.2.0
9.602 go: downloading github.com/skeema/knownhosts v1.3.0
9.610 go: downloading github.com/xanzy/ssh-agent v0.3.3
9.647 go: downloading github.com/cloudflare/circl v1.5.0
48.30 # github.com/coveooss/multilogger
48.30 /root/go/pkg/mod/github.com/coveooss/multilogger@v0.6.0/level.go:43:22: constant 4294967295 overflows int