Merge pull request #49 from LdDl/mxn-epoch

Epoch-based queries ManyToMany calls + Threadsafe API for them

Merge pull request #48 from LdDl/increment-upd

Incremental recustomization

Merge pull request #43 from LdDl/further-opts

Epoch-based queries, Non-threadsafe and threadsafe APIs

fix local nxm search

Clear code and add clarifications (#22)

* redudant AddVertex()

* merge relaxation and actual dijkstra

* count edges and shourtcuts on a fly + add getters

* redudant 'IsShortcut'

* organize heaps

* shorten

* rev names

* mv incident

* redudant NewVertex

* decrease vertex fields num

* rm heaps from graph

* name

* redudant nodeOrdering?

* run fmt

* pointer to incident edge

* rename

* merge relaxation and bi-dir search

* order could be int64, clarification about contraction id

* consider Goish loops

* continue goish loops

* merge checkID

* com

* clarify previousSourceID

* comment section

* comment section

* comment section

defer close + naming

update epoxrt functions

update shortcut getter

two new getters

num of shortcut increased (again)