Refactor parameter parsing to be more generic.

[syntaxseed]

Parameter parsing needs to be more generic to read any number of params & pass an array of them to the command.

[deziev]

implemented generic flag parser in #13

/**
 * Take every element from arg array with dash '-',
 * remove duplicates and invalid flags
 * 
 * @param {String[]} args In format ['ls', '-la', '/'] 
 * @param {String[]} supportedFlagsList Such as ['a', 'l]
 * @returns {Set}
 */

[syntaxseed]

Would be nice if commands could be passed an array or set of arrays with:

• command name
• array of flags
• array of non-flag parameters