[tests] Fix PATH use in tests.xml

Setting environment variables in <pre_steps /> has not effect - it is
evaluated in separate shell.

Relates NEMO#520
[tests] Do not hardcode variable paths

Relates NEMO#520
[tests] Fix lca-cita-test file permissions (+x)

Relates NEMO#520
[tests] testlib.sh: improve error reporting

Relates NEMO#520
[tests] Fix timing in respect to FS time resolution

Relates NEMO#520
[tests] Remove unused env.{py,sh}.in

env.py.in and env.sh.in have been left unused (not installed) since f79e5b1

Relates NEMO#520
[tests] Fix test-regexps

Relates NEMO#520
[tests] Allow to execute tests on target

Originally it was supposed tests would be executed inside build dir.

Relates NEMO#520
[lca-tool] Adapt to mlite no more using mlocale

mlite library no more relies on mlocale library to localize desktop
entry name and no alternative mechanism to implement the functionality
behind CONTENTACTION_L10N_PATH environment variable is provided by mlite
at the moment -- removing the feature.  To make 'lca-tool --l10n' tests
pass without the possibility to use CONTENTACTION_L10N_PATH, absolute
paths are specified for the X-MeeGo-Translation-Catalog key.

mlite passes '-' as 'prefix' to QTranslator::load() -- renaming files.

mlite uses qtTrId() -- translation catalogs must be 'id based'.

Relates NEMO#520
Merge pull request #2 from martyone/master

Fix tests