association_basics, updated how inverse_of works
association_basics, updated how inverse_of works

Fixed bug in the example code. A bit related to rails issue in
 https://github.com/rails/rails/issues/3223
koic/rails,shioyama/rails,mijoharas/rails,matrinox/rails,bradleypriest/rails,kddeisz/rails,kirs/rails-1,odedniv/rails,stefanmb/rails,gcourtemanche/rails,mathieujobin/reduced-rails-for-travis,starknx/rails,rossta/rails,kmayer/rails,illacceptanything/illacceptanything,illacceptanything/illacceptanything,palkan/rails,untidy-hair/rails,tijwelch/rails,esparta/rails,kmcphillips/rails,illacceptanything/illacceptanything,fabianoleittes/rails,kddeisz/rails,Envek/rails,travisofthenorth/rails,bogdanvlviv/rails,kddeisz/rails,kenta-s/rails,illacceptanything/illacceptanything,felipecvo/rails,gfvcastro/rails,mtsmfm/railstest,brchristian/rails,ngpestelos/rails,eileencodes/rails,alecspopa/rails,hanystudy/rails,voray/rails,utilum/rails,esparta/rails,iainbeeston/rails,sealocal/rails,aditya-kapoor/rails,yhirano55/rails,mohitnatoo/rails,ttanimichi/rails,illacceptanything/illacceptanything,notapatch/rails,utilum/rails,mohitnatoo/rails,illacceptanything/illacceptanything,assain/rails,rafaelfranca/omg-rails,lucasmazza/rails,illacceptanything/illacceptanything,lcreid/rails,eileencodes/rails,shioyama/rails,arjes/rails,sealocal/rails,mechanicles/rails,jeremy/rails,prathamesh-sonpatki/rails,gavingmiller/rails,illacceptanything/illacceptanything,xlymian/rails,Envek/rails,yawboakye/rails,printercu/rails,xlymian/rails,rbhitchcock/rails,BlakeWilliams/rails,odedniv/rails,elfassy/rails,Stellenticket/rails,MSP-Greg/rails,yalab/rails,odedniv/rails,repinel/rails,bogdanvlviv/rails,iainbeeston/rails,prathamesh-sonpatki/rails,yahonda/rails,deraru/rails,mijoharas/rails,mechanicles/rails,bolek/rails,iainbeeston/rails,rossta/rails,kamipo/rails,aditya-kapoor/rails,aditya-kapoor/rails,yalab/rails,Erol/rails,richseviora/rails,MichaelSp/rails,matrinox/rails,yahonda/rails,flanger001/rails,deraru/rails,lcreid/rails,fabianoleittes/rails,maicher/rails,amoody2108/TechForJustice,coreyward/rails,Edouard-chin/rails,shioyama/rails,gfvcastro/rails,koic/rails,starknx/rails,mechanicles/rails,ngpestelos/rails,richseviora/rails,MichaelSp/rails,yhirano55/rails,printercu/rails,88rabbit/newRails,joonyou/rails,tgxworld/rails,georgeclaghorn/rails,riseshia/railsguides.kr,vipulnsward/rails,brchristian/rails,Edouard-chin/rails,Stellenticket/rails,lcreid/rails,Vasfed/rails,notapatch/rails,palkan/rails,gcourtemanche/rails,tijwelch/rails,tjschuck/rails,kachick/rails,prathamesh-sonpatki/rails,yasslab/railsguides.jp,ttanimichi/rails,coreyward/rails,sealocal/rails,notapatch/rails,samphilipd/rails,marklocklear/rails,rails/rails,Erol/rails,georgeclaghorn/rails,flanger001/rails,joonyou/rails,mohitnatoo/rails,vassilevsky/rails,yhirano55/rails,kenta-s/rails,Vasfed/rails,samphilipd/rails,gauravtiwari/rails,samphilipd/rails,gauravtiwari/rails,schuetzm/rails,riseshia/railsguides.kr,mtsmfm/railstest,pvalena/rails,yawboakye/rails,starknx/rails,schuetzm/rails,alecspopa/rails,bradleypriest/rails,88rabbit/newRails,pschambacher/rails,felipecvo/rails,yahonda/rails,Stellenticket/rails,baerjam/rails,elfassy/rails,mtsmfm/rails,maicher/rails,travisofthenorth/rails,lcreid/rails,yasslab/railsguides.jp,mijoharas/rails,maicher/rails,illacceptanything/illacceptanything,utilum/rails,matrinox/rails,gfvcastro/rails,yawboakye/rails,MichaelSp/rails,repinel/rails,koic/rails,yhirano55/rails,lucasmazza/rails,bradleypriest/rails,BlakeWilliams/rails,pvalena/rails,assain/rails,kmcphillips/rails,illacceptanything/illacceptanything,bolek/rails,riseshia/railsguides.kr,BlakeWilliams/rails,hanystudy/rails,BlakeWilliams/rails,brchristian/rails,flanger001/rails,utilum/rails,jeremy/rails,yawboakye/rails,jeremy/rails,rafaelfranca/omg-rails,vipulnsward/rails,georgeclaghorn/rails,baerjam/rails,illacceptanything/illacceptanything,Spin42/rails,esparta/rails,illacceptanything/illacceptanything,illacceptanything/illacceptanything,ledestin/rails,richseviora/rails,MSP-Greg/rails,Erol/rails,schuetzm/rails,travisofthenorth/rails,ttanimichi/rails,arunagw/rails,alecspopa/rails,gauravtiwari/rails,kaspth/rails,yasslab/railsguides.jp,kaspth/rails,MSP-Greg/rails,tgxworld/rails,betesh/rails,vassilevsky/rails,eileencodes/rails,repinel/rails,kmayer/rails,betesh/rails,pschambacher/rails,repinel/rails,travisofthenorth/rails,kaspth/rails,mtsmfm/railstest,rails/rails,amoody2108/TechForJustice,kirs/rails-1,tjschuck/rails,stefanmb/rails,palkan/rails,yalab/rails,yahonda/rails,arunagw/rails,kamipo/rails,xlymian/rails,Envek/rails,aditya-kapoor/rails,bogdanvlviv/rails,eileencodes/rails,EmmaB/rails-1,Erol/rails,marklocklear/rails,betesh/rails,untidy-hair/rails,gfvcastro/rails,arjes/rails,baerjam/rails,illacceptanything/illacceptanything,rossta/rails,pvalena/rails,notapatch/rails,baerjam/rails,assain/rails,tijwelch/rails,joonyou/rails,pschambacher/rails,lucasmazza/rails,tgxworld/rails,sergey-alekseev/rails,palkan/rails,fabianoleittes/rails,gcourtemanche/rails,Sen-Zhang/rails,rbhitchcock/rails,amoody2108/TechForJustice,tgxworld/rails,mechanicles/rails,ngpestelos/rails,Envek/rails,riseshia/railsguides.kr,mtsmfm/rails,jeremy/rails,joonyou/rails,rails/rails,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