add lines from official codeigniter download

- Added lines from the zip of Codeigniter-3.1.2

ignore compile_commands.json

CMake may generate `compile_commands.json` file with `set(CMAKE_EXPORT_COMPILE_COMMANDS ON)` Option

Revert "添加DS_Store"

添加DS_Store

Added pattern for expex forward references

Existing .gitignore for vim incorrectly matched matched ".swq" through ".swz". 

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

Add zip and gzip extensions to Perl.gitignore

ExtUtils::MakeMaker based builds can generate .zip and .gz files

Add ehthumbs_vista.db as Windows thumbnail cache file

Standardize comment capitalization in go

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

Ignore wheels directory.

TeX: ignore endnotes *.ent files

As eggs/ directory, wheels directory may contain compiled wheels.

The `endnotes` package generates `*.ent` files. These should also be
ignored.

Symfony: Fix rule for backed up entities

Add missing beamer temporary file extension

Add missing beamer temporary file extension

Modified VS Code .gitignore

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

Replace DNX with .NET Core

Ignore *.ctxt in Java.gitignore

.ctxt files are generated automatically each time a project is compiled in BlueJ.

Removed bower asset exclusion

This is recommended by the Symfony docs:

http://symfony.com/doc/current/frontend/bower.html#should-i-git-ignore-or-commit-bower-assets

Change *.mtc patterns to single *.mtc[0-9]*

ignore Properties/launchSettings.json even if Properties is a subfolder