add Cli::Config and move Cli#account to Cli::Config
add Helper module for using helper methods and move existing helper methods there
add Cli::Config#read to read config file

* move configuration process there from #account
* move exception AccountError to Cli::Config from Cli
* change to use Config#read in Cli#run with Cli#configure
  * some tests need to use stub of #configure because config file is not existing
fix initiaization for Config@params to be Hash
add Config#num and #nest to get values for fetching logs

* now it returns only default values
add CLI general num setting
fix typo
add CLI general nest setting
improve Cli#num to be configured by any command
improve Cli#nest to be configured by any command
refactor Cli specs to reduce duplications
fix the bug on CLI that does not parse num and nest in #parse when it has no given nums

* because argv.shift.to_i whould be zero when it was nil
fix the bug on Cli that does not apply configured num and nest when input aliased command

* because Config#num, #nest did not consider aliases
* modify to translate aliased commands
refactor Cli using alias translation
modify readme
Merge pull request #4 from upinetree/develop

add CLI config functionality (num, nest)