Fixes bundler working directory path

This prevents to create .gem/ directories inside each Puppet modules and
really stores all gems in .bundled/ directory.
The plugin building fails when .gem/ directories are present.

Change-Id: I65847de308bd11e71a1710c1ffc41ea766fdbdc1

tox.ini

@@ -11,11 +11,9 @@ changedir = {toxinidir}/deployment_scripts/puppet/manifests
 whitelist_externals =
     bundle
     mkdir
-setenv =
-    GEM_HOME={toxinidir}/.bundled_gems
 commands =
     mkdir -p {toxinidir}/.bundled_gems
-    bundle install
+    bundle install --path {toxinidir}/.bundled_gems
     bundle exec rake test
 
 [testenv:heka]
@@ -24,11 +22,9 @@ changedir = {toxinidir}/deployment_scripts/puppet/modules/{envname}
 whitelist_externals =
     bundle
     mkdir
-setenv =
-    GEM_HOME={toxinidir}/.bundled_gems
 commands =
     mkdir -p {toxinidir}/.bundled_gems
-    bundle install
+    bundle install --path {toxinidir}/.bundled_gems
     bundle exec rake test
 
 [testenv:lma_collector]
@@ -37,11 +33,9 @@ changedir = {toxinidir}/deployment_scripts/puppet/modules/{envname}
 whitelist_externals =
     bundle
     mkdir
-setenv =
-    GEM_HOME={toxinidir}/.bundled_gems
 commands =
     mkdir -p {toxinidir}/.bundled_gems
-    bundle install
+    bundle install --path {toxinidir}/.bundled_gems
     bundle exec rake test
 
 [testenv:docs]
@@ -51,8 +45,13 @@ commands =
     make clean html SPHINXOPTS=-W
 
 [testenv:build_plugin]
+changedir = {toxinidir}
 whitelist_externals =
     fpb
+    rm
 commands =
+    rm -rf .build
+    rm -rf repositories/ubuntu/*.deb
+    rm -rf repositories/centos/*.rpm
     fpb --check {toxinidir} --debug
     fpb --build {toxinidir} --debug