Add 2 new classes and move code into them from autoload:
* NERDTree. Each nerdtree buffer now has a NERDTree object that holds
the root node and will old other util functions
* UI. Each NERDTree object holds a UI object which is responsible for
rendering, getting the current node, etc
Still a fair few methods to sort through in autoload (many of which will
end up in the above classes) - need sleep though.
On some new versions of vim these files were being loaded before the
main NERD_tree.vim which was causing errors as dependencies werent
loaded in time. Move the classes into lib - so vim wont try to load them
until we tell it
This is needed because some versions of vim dont let you chain method
calls together. So do the work in NERDTreeCreator instead of forcing all
callers to break the New().createXXX() calls out onto 2 lines with an
intermediate variable.
Fixes#226.
Add the NERDTreeCreator class.
Stick all functions related to creating a primary/secondary/mirror
nerdtree in there. We may break this down further in the future, but
this is a good starting point.
Make some of the interface binding functions in autoload/nerdtree
public. This is needed since we are accessing some of them from
NERDTreeCreator. Should be temporary until we get some kind of proper
interface binding system set up.
* Move the classes out into `plugin/nerdtree/<classname>`.
* Move the other functions out into `autoload/nerdtree.vim`.
Stuff still to do:
* extract out at least one view class from `autoload/nerdtree` -
something like NERDTreeWindow
* figure out which functions in autoload/nerdtree should be scoped to
the script instead of public
