### What changes were proposed in this pull request?
This patch converts CR/LF into LF in 3 source files, which most files are only using LF. This patch also add rules to enforce EOL as LF for all java, scala, xml, py, R files.
### Why are the changes needed?
The majority of source code files are using LF and only three files are CR/LF. While using IDE would let us don't bother with the difference, it still has a chance to make unnecessary diff if the file is modified with the editor which doesn't handle it automatically.
### Does this PR introduce any user-facing change?
No
### How was this patch tested?
```
grep -IUrl --color "^M" . | grep "\.java\|\.scala\|\.xml\|\.py\|\.R" | grep -v "/target/" | grep -v "/build/" | grep -v "/dist/" | grep -v "dependency-reduced-pom.xml" | grep -v ".pyc"
```
(Please note you'll need to type CTRL+V -> CTRL+M in bash shell to get `^M` because it's representing CR/LF, not a combination of `^` and `M`.)
Before the patch, the result is:
```
./sql/core/src/main/java/org/apache/spark/sql/execution/columnar/ColumnDictionary.java
./sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/optimizer/complexTypesSuite.scala
./sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/ComplexTypes.scala
```
and after the patch, the result is None.
And git shows WARNING message if EOL of any of source files in given types are modified to CR/LF, like below:
```
warning: CRLF will be replaced by LF in sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Analyzer.scala.
The file will have its original line endings in your working directory.
```
Closes#27365 from HeartSaVioR/MINOR-remove-CRLF-in-source-codes.
Authored-by: Jungtaek Lim (HeartSaVioR) <kabhwan.opensource@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
We have shell scripts and Windows batch files, so we should enforce proper EOL character.
Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>
Closes#2726 from sarutak/eol-enforcement and squashes the following commits:
9748c3f [Kousuke Saruta] Fixed make.bat
252de89 [Kousuke Saruta] Removed extra characters from make.bat
5b81c00 [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into eol-enforcement
8633ed2 [Kousuke Saruta] merge branch 'master' of git://git.apache.org/spark into eol-enforcement
5d630d8 [Kousuke Saruta] Merged
ba10797 [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into eol-enforcement
7407515 [Kousuke Saruta] Merge branch 'master' of git://git.apache.org/spark into eol-enforcement
772fd4e [Kousuke Saruta] Normized EOL character in make.bat and compute-classpath.cmd
ac7f873 [Kousuke Saruta] Added an entry for .gitattributes to .rat-excludes
1570e77 [Kousuke Saruta] Added .gitattributes
