CONTRIBUTING.md: Prohibit "+1" comments in favor of reactions
CONTRIBUTING.md: Prohibit "+1" comments in favor of reactions

Refs https://github.com/blog/2119-add-reactions-to-pull-requests-issues-and-comments
Refs https://github.com/dear-github/dear-github/issues/141#issuecomment-195106918
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IdanCo/bootstrap,andresgalante/bootstrap,vsn4ik/bootstrap,9-chirno/chirno,xt0rted/bootstrap,johnajacob/bootstrap,Delagen/bootstrap,fschumann1211/bootstrap,tagliala/bootstrap,igoynawamreh/bootstrap,JumpLinkNetwork/bootstrap-backward,tomlutzenberger/bootstrap,joblocal/bootstrap,Scoutski/bootstrap,SweetProcess/bootstrap,twbs/bootstrap,Lyricalz/bootstrap,JumpLinkNetwork/bootstrap-backward,creativewebjp/bootstrap,Hightrack/bootstrap,gijsbotje/bootstrap,supergibbs/bootstrap,frostbitten/bootstrap,zalog/bootstrap,johnajacob/bootstrap,SweetProcess/bootstrap,Lyricalz/bootstrap,zalog/bootstrap,hebbet/bootstrap,slavanga/bootstrap,johnajacob/bootstrap,frostbitten/bootstrap,Lyricalz/bootstrap,Hightrack/bootstrap,tibo66/bootstrap,jipexu/bootstrap,m5o/bootstrap,NCARB/bootstrap,lemuelbarango/bootstrap,creativewebjp/bootstrap,bardiharborow/bootstrap,Delagen/bootstrap,sealocal/bootstrap,SweetProcess/bootstrap,sealocal/bootstrap,fschumann1211/bootstrap,hebbet/bootstrap,janseliger/bootstrap,kvlsrg/bootstrap,creativewebjp/bootstrap,frostbitten/bootstrap,bootstrapbrasil/bootstrap,bardiharborow/bootstrap,coliff/bootstrap,n054/bootstrap,9-chirno/chirno,slavanga/bootstrap,inway/bootstrap,xt0rted/bootstrap,Hemphill/bootstrap-docs,copperdesign/bootstrap,abvalentine/bootstrap,hebbet/bootstrap,janseliger/bootstrap,jipexu/bootstrap,tibo66/bootstrap,vsn4ik/bootstrap,bardiharborow/bootstrap,IdanCo/bootstrap,nice-fungal/bootstrap,GerHobbelt/bootstrap,twbs/bootstrap,edanbarak/bootstrap,TheFridayInstitute/bootstrap,supergibbs/bootstrap,tagliala/bootstrap,edanbarak/bootstrap,n054/bootstrap,wesamco/bootstrap-rtl,wesamco/bootstrap-rtl,igoynawamreh/bootstrap,abvalentine/bootstrap,m5o/bootstrap,JumpLinkNetwork/bootstrap-backward,andresgalante/bootstrap,seanwu99/bootstrap,seanwu99/bootstrap,Scoutski/bootstrap,wesamco/bootstrap-rtl,Hemphill/bootstrap-docs,Hightrack/bootstrap,lemuelbarango/bootstrap,lemuelbarango/bootstrap,GerHobbelt/bootstrap,afuno/bootstrap,tomlutzenberger/bootstrap,GerHobbelt/bootstrap,stanwmusic/bootstrap,realcrowd/bootstrap,yuyokk/bootstrap,jipexu/bootstrap,stanwmusic/bootstrap,lipis/bootstrap,Hemphill/bootstrap-docs,lemuelbarango/bootstrap,bootstrapbrasil/bootstrap,NCARB/bootstrap,tibo66/bootstrap,tibo66/bootstrap,inway/bootstrap,realcrowd/bootstrap,davethegr8/bootstrap,n054/bootstrap,janseliger/bootstrap,inway/bootstrap,xt0rted/bootstrap,slavanga/bootstrap,Hemphill/bootstrap-docs,gijsbotje/bootstrap,JumpLinkNetwork/bootstrap-backward,copperdesign/bootstrap,yuyokk/bootstrap,afuno/bootstrap,stanwmusic/bootstrap,lipis/bootstrap,TheFridayInstitute/bootstrap,tagliala/bootstrap,n054/bootstrap,lipis/bootstrap,kvlsrg/bootstrap,frostbitten/bootstrap,yuyokk/bootstrap,vsn4ik/bootstrap,Scoutski/bootstrap,abvalentine/bootstrap,SweetProcess/bootstrap,stanwmusic/bootstrap,hebbet/bootstrap,yuyokk/bootstrap,creativewebjp/bootstrap,realcrowd/bootstrap,johnajacob/bootstrap,tomlutzenberger/bootstrap,joblocal/bootstrap,fschumann1211/bootstrap,realcrowd/bootstrap,edanbarak/bootstrap,sealocal/bootstrap,seanwu99/bootstrap,sealocal/bootstrap,andresgalante/bootstrap,davethegr8/bootstrap,Scoutski/bootstrap,peterblazejewicz/bootstrap,afuno/bootstrap,copperdesign/bootstrap,IdanCo/bootstrap,Lyricalz/bootstrap,wesamco/bootstrap-rtl,peterblazejewicz/bootstrap,davethegr8/bootstrap,bardiharborow/bootstrap,tjkohli/bootstrap,vsn4ik/bootstrap,gijsbotje/bootstrap,edanbarak/bootstrap,slavanga/bootstrap,fschumann1211/bootstrap,NCARB/bootstrap,lipis/bootstrap,andresgalante/bootstrap,9-chirno/chirno,abvalentine/bootstrap,davethegr8/bootstrap,gijsbotje/bootstrap,bootstrapbrasil/bootstrap,coliff/bootstrap,supergibbs/bootstrap,peterblazejewicz/bootstrap,igoynawamreh/bootstrap,tjkohli/bootstrap,TheFridayInstitute/bootstrap,nice-fungal/bootstrap,nice-fungal/bootstrap,afuno/bootstrap,igoynawamreh/bootstrap,kvlsrg/bootstrap,jipexu/bootstrap,Delagen/bootstrap,NCARB/bootstrap,9-chirno/chirno,joblocal/bootstrap,seanwu99/bootstrap,TheFridayInstitute/bootstrap,janseliger/bootstrap,IdanCo/bootstrap,Delagen/bootstrap,zalog/bootstrap,supergibbs/bootstrap,xt0rted/bootstrap,copperdesign/bootstrap,joblocal/bootstrap