Jenkinsfile: fix encouragement/dependency-check if

See merge request !33

minor change in diff jenkinsfile script

See merge request !28

upgrade checkstyle

See merge request !21

Add eclipse checkstyle file to .gitignore

See merge request !32

suggested in https://github.com/GIScience/oshdb/pull/376 by rtroilo

check dependencies only in main branch (e.g. main, master, …)

See merge request !31

don't send upgrade notifications when there are none

See merge request !30

ignore grep exit code during maven upgrade check

See merge request !29

which returns a nonzero exit code when the search expression was not found (e.g. if no plugins/dependencies have to be updated)

update parent to 2.10

See merge request !27

add custom checkstyle rule: avoid trailing whitespace

Closes #6

See merge request !24

added spotbugs and surefire to maven dependencies, updated spotbugs to 4.2.0

See merge request !26

[INFO] The following plugin updates are available:
[INFO]   com.github.spotbugs:spotbugs-maven-plugin .......... 3.1.7 -> 4.2.3
[INFO]   maven-checkstyle-plugin ............................ 3.1.1 -> 3.1.2
[INFO]   maven-compiler-plugin .............................. 3.8.0 -> 3.8.1
[INFO]   maven-pmd-plugin ................................. 3.11.0 -> 3.14.0
[INFO]   maven-surefire-plugin .......................... 2.22.2 -> 3.0.0-M5
[INFO]   org.sonarsource.scanner.maven:sonar-maven-plugin  3.7.0.1746 -> 3.9.0.2155
[INFO]   pl.project13.maven:git-commit-id-plugin ............ 4.0.3 -> 4.0.4

add general jenkins timeout

See merge request !25

add badges to Readme

See merge request !23

more precise project information in pom.xml

See merge request !22

* generic URL instead of SCM url
* SCM: use https for non-dev connection