Inconsistent icon for document-open and for document-open-recent about numix-folders

[dirtydancing]

To illustrate this issue with the example of Gedit in Ubuntu 14.10:

In the menu bar, the second icon from the left, apparently size 24, is "open a file" (text shown when hovering over). With Style No. 5, this is easily recognizable as a file, whereas e.g. in Style No. 6 and in Style No. 4 this is somewhat unclear.

Please also note that, when compared to the other icons, the folder icon size/shape fits best overall with Style No. 5 in this example, but again this might just come with the somewhat different intended designs of the Styles.

Finally, please note that the icon is the wrong one for Style No. 4, which has already been addressed in #25

Style No. 5 (correct)

Style No. 6 (questionable)

Style No. 4 (inconsistent)

[andia89]

Just a comment: merging my branch will not fully close this issue, since only style 2 is done at the moment. I got a little bit confused by the different bugs :)