_get_module_path() returns empty string when a module is not found
Add Vital.exists()
Use exepath which can be used after 7.4.235
Add Vital.search()
Data.List: Fix document of any() and or()
Merge pull request #154 from vim-jp/improve-vital-loader

Improve vital loader
Improve dependence specification
Merge pull request #156 from vim-jp/exepath

Use exepath which can be used after 7.4.235
Merge pull request #157 from vim-jp/optional-dependence

Improve dependence specification
Random.Xor128: Add generator object
Random.Xor128: Improve help
Random.Xor128: Rename new() to new_generator()
Merge pull request #158 from vim-jp/random

Random.Xor128: Add generator object
Random.Xor128: Fix an error
Cannot be import the module which is using the wild card for dependence
Fix a bug
Random: Add Random module
Random: Tweaks the document
Random: Fix sample()
Random: Add some examples to the document