tiny changes about fixing evaluation order

[author-y]

I have used this application in Ubuntu 20.04. In using this, there is some problem below.

1. In running gyazo from command line, I get the following error almost every time and sometimes it stops.
   error: process ID list syntax error
   (maybe this is related to import-im6.q16: unable to grab mouse #166 .)
2. In capturing the screen, the first capturing makes no sense and only the second capturing is used for generating figure. This happened both when I started it from the command line and when I started it from the Unity launcher.

By this pull request, 1. and 2. will be resolved. Each commit fixed the above problems, respectively in my environment.
I think this problem is related to the evaluation order of the variables in ruby.