AVRO-2531: Update commons-compress to version 1.19

(cherry picked from commit bd559d6)

AVRO-2531: Update commons-compress to version 1.19

(cherry picked from commit bd559d6)

AVRO-2528: Exclude test resources from license check

(cherry picked from commit 94923cf)

Preparing for release 1.9.1

AVRO-2386: Make customEncode and customDecode public (apache#511)

* Make customEncode and customDecode methods public

* Make methods in superclass public

(cherry picked from commit e250dcc)

AVRO-2386: Make customEncode and customDecode public (apache#511)

* Make customEncode and customDecode methods public

* Make methods in superclass public

(cherry picked from commit e250dcc)

Also exclude the new sums from being re-summed

(cherry picked from commit 0c63678)

AVRO-2383: NPE during Schema.applyAliases (apache#510)

(cherry picked from commit 196777c)

[AVRO-XXX] Update the Dist readme

Avro 1.8.2 release.