This commit ensures that when trying to parse the version of a tool
the comparison is done with the longest match for the given regular
expression. This solves cases such in `grub2` where the tool name
already provides some digit that could be seen as a version.
With the new Fstab class from prior pull request there is an
opportunity to handle all fstab related actions to be done
by that class. This commit extends the Fstab class with an
add_entry method such that we can avoid the extra lists
holding raw fstab lines in e.g the disk builder. In the end
all fstab related data is stored in an instance of the Fstab
class. This also extends the KIWI api by an fstab management
class. Related to #1329 and #1349
Handling of fstab should be done in its own namespace and class.
The current handling of fstab entries is spread at several places.
There should be only one code that writes the fstab entries and
that code should also care for the correct canonical order of
the mountpoints
This commit refactors the use of Path.which in several parts of the
code. Since dd4d2ed78 the Path utility is capable to run Path.which
on certain chroot env, thus no need to adapt the PATH environment
variable.
Fixes#1281
