improve language for gcm docs
improve language for gcm docs

Hasimir/cryptography,Ayrx/cryptography,Lukasa/cryptography,kimvais/cryptography,kimvais/cryptography,sholsapp/cryptography,bwhmather/cryptography,skeuomorf/cryptography,dstufft/cryptography,glyph/cryptography,dstufft/cryptography,bwhmather/cryptography,Lukasa/cryptography,skeuomorf/cryptography,dstufft/cryptography,Lukasa/cryptography,skeuomorf/cryptography,sholsapp/cryptography,sholsapp/cryptography,Ayrx/cryptography,Hasimir/cryptography,dstufft/cryptography,sholsapp/cryptography,glyph/cryptography,Ayrx/cryptography,bwhmather/cryptography,kimvais/cryptography,bwhmather/cryptography,Hasimir/cryptography,Ayrx/cryptography,skeuomorf/cryptography,dstufft/cryptography,Hasimir/cryptography,kimvais/cryptography