Scala.gitignore currently has more entries for SBT than SBT.gitignore itself.
Copy missing entries here.

In newer versions of the IntelliJ platform (such as the one used for Rider), the .idea files are now placed in a subdirectory of the same, named after the current project (such as ".idea/.idea.Everlook/.idea/workspace.xml"). Adding a double-star pattern to these folder rules will also ignore these new files and maintain backwards compatibility with previous revisions of this file.

Package Control now has a number of bundles for certificates instead
of the old directory. This ignores them as per

http://github.com/wbond/package_control/issues/1153
https://forum.sublimetext.com/t/generating-oscrypto-ca-bundle-crt-after-mac-os-install-and-security/23020

from the author

While will never be generated by the vim source code.
http://unix.stackexchange.com/questions/326707/vim-what-are-all-the-possible-swapfile-extensions

As Windows Vista Media Center thumbnails

References:

- https://nctritech.wordpress.com/tag/ehthumbs_vista-db/
- https://thumbsviewer.github.io/
- https://www.file-extensions.org/db-file-extension-windows-thumbnail-database

Added extensions.json as exception in .vscode folder. File is used as
extensions recommendation for project.

Read more here: https://www.gnu.org/software/emacs/manual/html_node/emacs/Directory-Variables.html

The IPython Notebook is now known as the Jupyter Notebook (see http://ipython.org/notebook.html). Jupyter ignore values are already found in the Python.gitignore.

Added datasource folder

Official docs, found here:
https://intellij-support.jetbrains.com/hc/en-us/articles/206544839 (as
of 13 Aug 2016)

Apple renames OS X to macOS. Announced @ WWDC 2016

This file as documentation (which seems lacking) states is used for calling custom Maven goals from the IDE.
Ignoring this file was a source much confusion in few projects (mapping Run action to custom goals... etc etc) 
Also this file does anything worth ignoring
Added by #145
Exclusion of `nbactions.xml`  from `.gitgnore` should be discussed.

Add exclusion for Scala IDE specific .cache-main files.

Visual Studio Code has a few files that can be placed into the workspace
in order to share settings across users.  Settings.json is for project
specific overrides.  Tasks.json is for executable tasks (build, gulp, etc.)
While launch.json is for debugging specific tasks.

.com.apple.timemachine.donotpresent is a system file created by TimeMachine on OSX by user choice.

Added auto-generated tag files.

These files differ on Windows and OS X.

Anything matched by `*.un~` will also be matched by the last rule, `*~`.

Code Recommenders introduced in Eclipse Luna (4.5) creates a .recommenders directory at the root of the workspace, like .metadata

The server-auth-dir is where Emacs stores authentication files for Emacs
servers (running over TCP). These are (usually) ephemeral in nature, and
should be ignored.

Just added some comments. Some of us don't need some of the lines in the file.

On systems that require a lib64, virtualenv creates a symlink to the local lib.

Remove .gradle because it is not eclipse specific and already added in Gradle.gitignore.