Add Alpine variant to Dockerfile examples

Signed-off-by: J0WI <J0WI@users.noreply.github.com>

.examples/dockerfiles/cron/fpm-alpine/Dockerfile

+FROM nextcloud:fpm-alpine
+
+RUN apk add --no-cache supervisor \
+  && mkdir /var/log/supervisord /var/run/supervisord
+
+COPY supervisord.conf /etc/supervisor/supervisord.conf
+
+ENV NEXTCLOUD_UPDATE=1
+
+CMD ["/usr/bin/supervisord"]

.examples/dockerfiles/cron/fpm-alpine/supervisord.conf

+[supervisord]
+nodaemon=true
+logfile=/var/log/supervisord/supervisord.log
+pidfile=/var/run/supervisord/supervisord.pid
+childlogdir=/var/log/supervisord/
+logfile_maxbytes=50MB                           ; maximum size of logfile before rotation
+logfile_backups=10                              ; number of backed up logfiles
+loglevel=error
+
+[program:php-fpm]
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+command=php-fpm
+
+[program:cron]
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+command=/cron.sh

.examples/dockerfiles/full/fpm-alpine/Dockerfile

+FROM nextcloud:fpm-alpine
+
+RUN set -ex; \
+    \
+    apk add --no-cache \
+        ffmpeg \
+        samba-client \
+        supervisor \
+#       libreoffice \
+    ;
+
+RUN set -ex; \
+    \
+    apk add --no-cache --virtual .build-deps \
+        $PHPIZE_DEPS \
+        imap-dev \
+        krb5-dev \
+        libressl-dev \
+        samba-dev \
+        bzip2-dev \
+        gmp-dev \
+    ; \
+    \
+    docker-php-ext-configure imap --with-kerberos --with-imap-ssl; \
+    docker-php-ext-install \
+        bz2 \
+        gmp \
+        imap \
+    ; \
+    pecl install smbclient; \
+    docker-php-ext-enable smbclient; \
+    \
+    runDeps="$( \
+        scanelf --needed --nobanner --format '%n#p' --recursive /usr/local/lib/php/extensions \
+            | tr ',' '\n' \
+            | sort -u \
+            | awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
+    )"; \
+    apk add --virtual .nextcloud-phpext-rundeps $runDeps; \
+    apk del .build-deps
+
+RUN mkdir -p \
+    /usr/share/man/man1 \
+    /var/log/supervisord \
+    /var/run/supervisord \
+;
+
+COPY supervisord.conf /etc/supervisor/supervisord.conf
+
+ENV NEXTCLOUD_UPDATE=1
+
+CMD ["/usr/bin/supervisord"]

.examples/dockerfiles/full/fpm-alpine/supervisord.conf

+[supervisord]
+nodaemon=true
+logfile=/var/log/supervisord/supervisord.log
+pidfile=/var/run/supervisord/supervisord.pid
+childlogdir=/var/log/supervisord/
+logfile_maxbytes=50MB                           ; maximum size of logfile before rotation
+logfile_backups=10                              ; number of backed up logfiles
+loglevel=error
+
+[program:php-fpm]
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+command=php-fpm
+
+[program:cron]
+stdout_logfile=/dev/stdout
+stdout_logfile_maxbytes=0
+stderr_logfile=/dev/stderr
+stderr_logfile_maxbytes=0
+command=/cron.sh

.examples/dockerfiles/imap/fpm-alpine/Dockerfile

+FROM nextcloud:fpm-alpine
+
+RUN set -ex; \
+    \
+    apk add --no-cache --virtual .build-deps \
+        $PHPIZE_DEPS \
+        imap-dev \
+        krb5-dev \
+        libressl-dev \
+    ; \
+    \
+    docker-php-ext-configure imap --with-kerberos --with-imap-ssl; \
+    docker-php-ext-install imap; \
+    \
+    runDeps="$( \
+        scanelf --needed --nobanner --format '%n#p' --recursive /usr/local/lib/php/extensions \
+            | tr ',' '\n' \
+            | sort -u \
+            | awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
+    )"; \
+    apk add --virtual .nextcloud-phpext-rundeps $runDeps; \
+    apk del .build-deps

.examples/dockerfiles/smb/fpm-alpine/Dockerfile

+FROM nextcloud:fpm-alpine
+
+RUN apk add --no-cache samba-client