Add Docker support

This commit adds a Dockerfile that can be used to build a Docker image
for running LSTU. A minimal configuration file is provided to help new
users get up and running with a minimal amount of effort.
9 jobs from docker-support-dev in 10 minutes and 58 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Sqlite
passed #129903
sqlite1

00:03:20

passed #129904
sqlite2

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passed #129905
sqlite3

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  Postgresql
passed #129906
postgresql1

00:03:42

passed #129907
postgresql2

00:03:42

passed #129908
postgresql3

00:03:46

 
  Mysql
passed #129909
mysql1

00:00:57

passed #129910
mysql2

00:00:57

passed #129911
mysql3

00:03:43