Development_Setup.rst: Update docs generation
Development_Setup.rst: Update docs generation

Updates the command for generating docs.

Closes coala/coala#5062

jayvdb/coala,coala/coala,SanketDG/coala,coala-analyzer/coala,SanketDG/coala,jayvdb/coala,coala-analyzer/coala,jayvdb/coala,coala-analyzer/coala,SanketDG/coala,coala/coala,coala/coala