[FIX] remove unused code

Remove code  that not used.
Also remove global veriable, introduced by this code
Also there was error when using custom currency (one not in 'currencies_all_keyed' map)
[FIX] Gruntfile: Add support for running devserver
[TASK] Package.json: Add shell to dependencies
Merge pull request #1790 from yongsoo/fix/grunt

[FIX] Gruntfile: Add support for running devserver
Merge pull request #1787 from darkdarkdragon/develop-fix-trust-1

[FIX] removed unused code
[FEATURE] RT-2447: BRL Tab
Merge pull request #1791 from Mesrop/develop-RT-2447-BRL-30-10

[FEATURE] RT-2447: BRL Tab
[FEATURE] RT-2501: MXN tab