[vala] (14 commits) Non-fast-forward update to branch wip/ci

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/ci' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  e153f32... coverage: Build gidl-bindings
  7e753b8... ci: Add .gitlab-ci.yml
  92f6936... ci: Add ubuntu:16.04 run with gcc
  6a77658... ci: Add ubuntu:18.04 run with gcc
  f90a900... ci: Add fedora:rawhide run with clang
  b6161be... ci: Add archlinux/base:latest run with gcc
  35e7309... ci: archlinux/bison - https://bugs.archlinux.org/task/64165
  89a0651... ci: Add alpine:edge run with gcc
  360d979... ci: Always deploy

Commits added to the branch:

  48f9982... Add TraverseVisitor for traversing the tree with a callback (*)
  647b55d... vala: Move transformation of unary increment/decrement to c (*)
  cb1828c... Force usage of temporary variables for "tainted" member acc (*)
  8bab9d1... tests: Add "pre-post-increment with side effect" tests to i (*)
  254431c... vala: Set parent_node for child nodes of lambda-expression (*)
  c12fd37... coverage: Build gidl-bindings
  311d91c... ci: Add .gitlab-ci.yml
  2460b6c... ci: Add ubuntu:16.04 run with gcc
  fb9b391... ci: Add ubuntu:18.04 run with gcc
  7d2f459... ci: Add fedora:rawhide run with clang
  96c3077... ci: Add archlinux/base:latest run with gcc
  0e90ce1... ci: archlinux/bison - https://bugs.archlinux.org/task/64165
  0df6f55... ci: Add alpine:edge run with gcc
  f9e161e... ci: Always deploy

(*) This commit already existed in another branch; no separate mail sent