This patch adds missing newlines, trims multiple redundant final
newlines into a single one, and trims redundant leading newlines in all
*.phpt sections.

According to POSIX, a line is a sequence of zero or more non-' <newline>'
characters plus a terminating '<newline>' character. [1] Files should
normally have at least one final newline character.

C89 [2] and later standards [3] mention a final newline:
"A source file that is not empty shall end in a new-line character,
which shall not be immediately preceded by a backslash character."

Although it is not mandatory for all files to have a final newline
fixed, a more consistent and homogeneous approach brings less of commit
differences issues and a better development experience in certain text
editors and IDEs.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206
[2] https://port70.net/~nsz/c/c89/c89-draft.html#2.1.1.2
[3] https://port70.net/~nsz/c/c99/n1256.html#5.1.1.2

This patch simplifies line endings tracked in the Git repository and
syncs them to all include the LF style instead of the CRLF files.

Newline characters:
- LF (\n) (*nix and Mac)
- CRLF (\r\n) (Windows)
- CR (\r) (old Mac, obsolete)

To see which line endings are in the index and in the working copy the
following command can be used:
`git ls-files --eol`

Git additionally provides `.gitattributes` file to specify if some files
need to have specific line endings on all platforms (either CRLF or LF).

Changed files shouldn't cause issues on modern Windows platforms because
also Git can do output conversion is core.autocrlf=true is set on
Windows and use CRLF newlines in all files in the working tree.

Unless CRLF files are tracked specifically, Git by default tracks all
files in the index using LF newlines.

* PHP-7.1:
  Fix #76704: mb_detect_order return value varies based on argument type

php_mb_parse_encoding_list() and php_mb_parse_encoding_array() are
supposed to return SUCCESS and FAILURE, not 1 and 0, respectively.

* PHP-7.1:
  Fix #75944: Wrong cp1251 detection

`\xFF` is a valid character of CP-1251.