[avr] Removed usage of deprecated MCUSR

Since avr-libc 1.8.0 MCUSR is marked as poison as it was replaced by the
correct name MCUCSR.
Thus code still using the old MCUSR name does not compile anymore.

This commit replaces usages of former MCUSR by its new name MCUCSR and
modifies the alias fallback accordingly.
Output sha1sums of files used for simulation on fail
This helps reproducing results from the CI
Support setting the RELSTR
To build identical binaries the RELSTR must be identical, too.
Always compile verbose when running the CI
Merge pull request #821 from cmorty/pull/ci_debug

Make reproducing result from the CI easier
Merge pull request #782 from ejoerns/pull-req/avr-mcucsrfix

[avr] Removed usage of deprecated MCUSR
Initial commit for build.gradle

- Migrate COOJA source and some apps to a standard directory layout
- Can download dependencies dynamically
- Can check style (Android style guide)
- Can generate configuration files for idea and eclipse IDE
- Adding gradle build files to .gitignore
- Removed all bundled libraries
- All regression tests are now using gradle to build cooja
- Migrated apps to gradle for building (embedded libs have been removed)
- run commands are now available as well. For instance to limite max
  Heap memory
configured gradle for Cooja's mspsim extension
Simplify mspsim build.gradle
gradle --no-color in travis
compile mspsim.jar, fail on copy if sources are non-existant
sourceSets still needed; cooja_mspsim.jar is empty
Adding tasks descriptions and cleared some tasks
Adding dependencie for jdesktop