ORC-766: Generalize the docker scripts to handle build arguments.

[omalley]

What changes were proposed in this pull request?

This replaces the build matrix loops in the docker reinit.sh and run-all.sh scripts with expanding the
versions that we want to build in os-list.txt. The pattern for the build args is based on the name:

ubuntu20 builds ubuntu 20 with default parameters jdk=8 and cc=gcc
ubuntu20_jdk=11_cc=clang builds ubuntu 20 with jdk=11 and cc=clang

Those names are carried through to the docker tags with s/=/-/.

How was this patch tested?

I ran reinit.sh and run-all.sh and both ran fine. The docker images default to the proper c++ and java compilers.

[dongjoon-hyun]

+1, LGTM. It's a nice generalization!
I tested this locally.

Building centos7
Building centos8
Building debian9
Building debian10
Building ubuntu16
Building ubuntu18
Building ubuntu20
Building centos8_jdk=11
Building ubuntu20_jdk=11
Building ubuntu20_jdk=11_cc=clang
Launching centos7 as 166755
Launching centos8 as 166756
Launching debian9 as 166757
Launching debian10 as 166758
Launching ubuntu16 as 166759
Launching ubuntu18 as 166760
Launching ubuntu20 as 166761
Launching centos8_jdk=11 as 166762
Launching ubuntu20_jdk=11 as 166764
Launching ubuntu20_jdk=11_cc=clang as 166767

$ docker run -it --rm orc-ubuntu20_jdk-11 java -version
openjdk version "11.0.10" 2021-01-19
OpenJDK Runtime Environment (build 11.0.10+9-Ubuntu-0ubuntu1.20.04)
OpenJDK 64-Bit Server VM (build 11.0.10+9-Ubuntu-0ubuntu1.20.04, mixed mode, sharing)