Bug 935059 - Add partial FOTA support

Add --fota-type and --fota-files arguments to script to handle the
generation of a limited subset of the FOTA. With fota_type 'full', code
path should remain the same. But with 'partial', we will:
 - not format the partition
 - purge the directory specified in --fota-dirs
 - only get the files specified in the file specified as --fota-files
   argument
Add nexus-5 support. r=mwu
Merge pull request #303 from lissyx/bug935059

Bug 935059 - Add partial FOTA support r=gsvelto
Merge pull request #311 from Seinlin/master

Add nexus-5 support.
Bug 948774: Default to not waiting for files from the Nuwa process since it is frozen. r=fabrice
Merge pull request #306 from khuey/nuwa

Bug 948774: Default to not waiting for files from the Nuwa process since...
Merge pull request #314 from jld/profile-capture-nonmainproc

Bug 921165: allow ./profile.sh capture if only non-main processes are profiled
Bug 946407: Accept a single unified-memory-report file.

Using nsIMemoryReporterManager::GetReports to get memory reports from
content processes means that we have a single collection of report
entries instead of one per process, which means a single file.  But this
code has to deal with geckos both before and after that patch.  So,
this change accepts either N individual "memory-report-*" files or one
"unified-memory-report-*" file (and applies this more generally, because
that was easier than making it specific to the main memory report).