install with force-latest should not update bower.json

[himdel]

Output of bower -v && npm -v && node -v:

1.7.9
3.10.5
v6.0.0

Steps to reproduce the issue:

1. Have a conflict that needs a resolution
2. Run bower install -F
3. see that bower.json got changed

Describe the results you received:

Bower automatically picks a sane resolution (good), but it stores that resolution in bower.json (bad).
There seems no way to prevent bower from saving that resolution.

Describe the results you expected:

I would expect bower to save the resolution only when --save (or something similar) is used together with --force-latest, not by default.

Or, a way to prevent that behaviour.

Additional information:

Looks like it was introduced in #862 , to fix #861, but #861 does mention expecting that behaviour only with save: true.

The reason I'm asking for this is that we're always using bower install -F in our scripts, since most of the developers are not frontend developers and can't be expected to know better than bower (also, CI). And this works just fine... Except then you get a conflict, and suddenly everybody starts commiting resolutions which are unnecessary since you'll mostly get a sane one using -F anyway, and then somebody needs to clean it up when that resolution becomes obsolete and actively wrong..