Merge/dev to fork master merge

See merge request !11

Allow connection endpoints for list nonterminals

See merge request !10

# Conflicts:
#	ragconnect.base/src/main/resources/ragConnectVersion.properties

Version 0.3.1

See merge request !8

Resolve "Check input for URI format upon calling a connect method"

See merge request !7

Update relast-preprocessor to newest version.

See merge request !6

- begin with support for multi-file errors

- different mqtt port not testable using current CI setup (only port 1883 exposed in image)
- print compiler error messages in single log output statement

- fix bug in getSecondMqttHost
- remove dependency to log4j
- use java.util.logging in Compiler
- add flag --experimental-jastadd-329 to enable behaviour using an unpublished JastAdd version with solution for issue 329

- see #23

Testing incremental dependency tracking.

See merge request !5

Resolve "Subtree update"

See merge request !4

Resolve "Use updated testing plugin"

See merge request !3

Resolve "Missing default mapping for boolean"

See merge request !2

- add tests for boolean case
- expose default mappings in TestUtils
- fix problem with resolving grammar files too early

Resolve "Repo documentation"

See merge request !1