Update 06-expressions.md
Update 06-expressions.md

Inserted two missing instances of the word "the".
Corrected "invokeDynamic" to "applyDynamic".
lrytz/scala,felixmulder/scala,shimib/scala,slothspot/scala,slothspot/scala,lrytz/scala,scala/scala,lrytz/scala,jvican/scala,felixmulder/scala,felixmulder/scala,slothspot/scala,jvican/scala,felixmulder/scala,martijnhoekstra/scala,shimib/scala,scala/scala,slothspot/scala,felixmulder/scala,shimib/scala,lrytz/scala,scala/scala,martijnhoekstra/scala,felixmulder/scala,jvican/scala,martijnhoekstra/scala,scala/scala,jvican/scala,scala/scala,lrytz/scala,shimib/scala,lrytz/scala,scala/scala,slothspot/scala,slothspot/scala,jvican/scala,felixmulder/scala,martijnhoekstra/scala,jvican/scala,martijnhoekstra/scala,jvican/scala,shimib/scala,slothspot/scala,martijnhoekstra/scala,shimib/scala