Fix typos and grammar issues in comments

[alexandear]

This PR fixes issues in comments:

• Typos in words.
• Use a comma before 'so' if it connects two independent clauses (unless they are closely connected and short). 
• This word is normally spelled with a hyphen.
• Use a comma before 'or' if it connects two independent clauses (unless they are closely connected and short). 
• Use an instead of 'a' if the following word starts with a vowel sound, e.g. 'an article', 'an hour'. 
• Did you mean past? 
• Consider using either the past participle filed or the present participle filing here. 
• Consider using many. 
• When '64-bit' is used as a modifier, it is usually spelled with a hyphen. 
• The past participle is required after "must be", alternatively you could omit the "be". 

[Syfaro]

Mostly looks good, I think there's one thing that wasn't quite correct.

I also quite substantially updated the master branch, so it might take a little bit of messing around to get it into a state where it can be merged again, sorry!

[alexandear]

@Syfaro I updated PR, please recheck

[Syfaro]

Looks good, thanks!