Fix multi-language settings for tinyMCE

I need these.
Please...
Fix tinymce lang file path to define EDITOR_LANGUAGE
Merge pull request #1 from hissy/localize-tinymce-fix

Fix tinymce lang file path to define EDITOR_LANGUAGE
Enable using dots and underscores in usernames

Let's enable using dots and underscores in the user names. Those 'special'
characters should only be present in the middle of usernames, so
'john.doe' is valid, '.johndoe' is invalid.
Let formatSize return a specific size

Extend NumberHelper->formatSize(): now we can specify a specific unit.
For instance: formatSize(1024) returns '1.00 KB',
but formatSize(1024, 'bytes') returns '1,024 bytes'
Use NumberHelper->formatSize when formatting file sizes
Merge pull request #1594 from mlocati/use-numberhelper-formatsize

Use NumberHelper->formatSize
Merge branch 'multi-language-settings-for-tinyMCE' of https://github.com/tao-s/concrete5 into tao-s-multi-language-settings-for-tinyMCE
build updates, merging TinyMCE
Revert "build updates, merging TinyMCE"

This reverts commit 88690f0c27c71abb03c885af0d912ed0f6a27f69.
Revert "Revert "build updates, merging TinyMCE""

This reverts commit 9ddaba64328c3a664b3f05047233f23ea4c6fb1b.
Reverting a previous pull request's impact points by hand because git fucking sucks.
Keep original file name when importing files
fixing issue with unsanitized cID parameter in request library
Add Localization::activeLocale()

We should determine the active language dynamically.
So, let's introduce Localization::activeLocale() that should be used
instead of LANGUAGE
Add file/directory existance checks to grunt

Add functions to simply check if a file and/or a directory exists.

Example:
var c5fs = require('libraries/fs');
var isDirectory = c5fs.isDirectory(path);
var isFile = c5fs.isFile(path);
var isFileOrDirectory = c5fs.fileExists(path);
Reverting always showing installation languages in English
Merge branch 'multibyte-file-importer' of https://github.com/hissy/concrete5 into hissy-multibyte-file-importer
Merge pull request #1541 from mlocati/username-with-dots-and-underscores

Enable using dots and underscores in usernames
updating user error message