Merge pull request #100 from JohnTheGr8/master

Improvements for Firefox bookmarks
close #21 Allow user to set their custom ActionKeyword
Merge branch 'master' of https://github.com/qianlifeng/Wox.git
Some plugin style changes.
Move CMD settings to CMD plugin details.
Add Executable Plugin Loader
Refactoring Plugin Loader [WIP].
Update README.md
Update README.md
Refactoring [WIP]
Add portable python environment
Add missing files.
Add v2ex python plugin demo.
Add HackerNews python plugin as the Demo.
[WebSearch] Fix MessageBox behaviour

Fix MessageBox asking user to select item if he clicks No.
[Programs] Fix MessageBox behaviour

Fix MessageBox asking user to select item if he clicks No after trying
to Delete an item in Programs Settings.
Fix spelling mistake

seleted => selected
Implement #15
Merge pull request #105 from CoenraadS/master

[WebSearch/Programs] Fix MessageBox behaviour
Cosmetic changes

Taskbar Setting => Settings

Alignment of combo boxes
Alignment of checkboxes and text