Change relative_link description

Just to make its purpose a bit clearer, if my understanding is correct - it doesn't seem to be documented elsewhere yet.
Merge pull request #2 from bburns/patch-1

Change relative_link description
Merge branch 'master' of https://github.com/hexojs/site
Merge branch '2.8'
Update date of "Hexo 2.8 Released"
Modify image path
Update writing.md
Merge pull request #4 from thenoelforte/master

Update writing.md
Update API doc
Update doc: Helper
Update pagination.md
Proofing on docs index
Proofing on Setup docs
Proofing on Configuration docs
Proofing on Commands docs
Node should be latest stable version (0.10)
Merge pull request #6 from jonscottclark/master

Cleanup & clarification on some docs
Update writing.md

fixes typo in excerpts section
Merge pull request #7 from jimthedev/patch-1

Update writing.md
Merge pull request #5 from fiammanda/patch-1

Update pagination.md