enhance: Add comprehensive .gitignore for deb-mock project

- Add mock-specific build artifacts (chroot/, mock-*, mockroot/)
- Include package build files (*.deb, *.changes, *.buildinfo)
- Add development tools (.coverage, .pytest_cache, .tox)
- Include system files (.DS_Store, Thumbs.db, ._*)
- Add temporary and backup files (*.tmp, *.bak, *.backup)
- Include local configuration overrides (config.local.yaml, .env.local)
- Add test artifacts and documentation builds
- Comprehensive coverage for Python build system project

This ensures build artifacts, chroot environments, and development
tools are properly ignored in version control.

docs/Release-Notes-1.4.18.md

@@ -0,0 +1,41 @@
+---
+layout: default
+title: Release Notes 1.4.18
+---
+
+Released on 2019-08-27.
+
+## Mock-core-configs new features:
+
+ * New configs for RHEL. See [separate page](Feature-rhelchroots) for more info.
+ * Fedora 31 has been added
+ * Add local-source repo definition to Fedora Rawhide.
+ * revert sysusers setting [RHBZ#1740545](https://bugzilla.redhat.com/show_bug.cgi?id=1737469)
+
+## Mock new features and bugfixes:
+
+ * When a foreign architect is detected, Mock will automatically enable `--forcearch`.
+ * Support for subscription-manager has been added. See [RHEL chroots](Feature-rhelchroots) page.
+ * bootstrap-chroot always explicitly install shadow-utils
+ * Add [procenv plugin](Plugin-ProcEnv.md) for more detailed build time information. This plugin is disabled by default.
+ * Resolved issues with SELinux from the previous release. You may still experience some warnings, but none of them should be fatal.
+ * SIGTERM, SIGPIPE, and SIGHUP signals are now propagated to chroot.
+
+## Future
+
+Note that in upcoming versions, I would like to:
+
+ * drop python2 support as even EL7 version is running on python3 now.
+ * drop EL7 support (likely spring 2020). I mean to stop building Mock for EL7. Building packages for EL7 using Mock will be still supported.
+ * make DNF default package manager. E.g., you will have to state in the config that you want to use yum explicitly.
+
+Following contributors contributed to this release:
+
+* Dominik Turecek
+* Jan Buchmaier
+* Jiri Konecny
+* Miro Hrončok
+* Pat Riehecky
+* Pavel Raiskup
+
+Thank you.